Exhaust upgrade, the installation

Well today was pipe replacement time. Noise is much the same at idle, though gets fairly loud as rpm increases, no drone though. Im not sure how restrictive the current resonators and muffler is but things have changed for the better anyway.
Basically I had to pull timing at 2000rpm but now I can put it all back in. This may indicate that the smaller exhaust was optimising things around 2000rpm, whereas now its up at 4000rpm. The car definately seems to rev freer and my logging with the wideband has indicated at high map points that up to 5% more fuel is required. I need to fill in the map to get a good idea, but lower map points look much the same, its just the higher ones which need more fuel.
My timing table is out now, so I have started again with a combination table of a stock hsv gts and my previous table. It will take a good few sessions of logging and adjusting to get an idea of where things are now, however I did a WOT pull to 6300 and am still only making 0.82g/cyl or 300g/sec of air. By way of contrast the stock MAF max's out at 511g/sec intake KPa was 99 from a barometric of 101, so intake looks good.

Other than a full replacement exhaust and a Fast90/90 setup, which will both cost megabucks, Im done with the mods. Did a 0-60 to test today, but zero traction in 1st. So will try again another time. Still not thinking about a 402 stroker!

The search for the missing millions.

Well Ive been still thinking about where my percieved power loss is. In theory I should have gone from around 240rwkw to around 300rwkw from heads and cam change. Thats like 100bhp increase. However to me it only felt like maybe half that.

I reread this article here and set off to Simpson Race Exhausts in Berkshire. I had previously noted a smaller section of pipe going from the headers into the cats. They were excellent, do great work at a reasonable price and were very helpful.

Well Im booked in there next week for the bypass pipes. Looking at this pic below from popular hotrodding, noted in the link above. I can calculate my current bhp per cfm at 1.44 (500fwhp) Shocking, as its right off the left hand side of the page! Perhaps somewhere around 70% of Max. Stock it would have been around 1.6 (430fwhp) so thats bad enough, but maybe only 10% down 30% is not acceptable.
So without getting too excited I believe I can say Im definately going to pick a good bit of power up with the exhaust upgrade. It should also definately allow a little more timing, or at least reduce the propensity to knock.

On a more serious topic, Ive been starting to have unclean thoughts about 402 and/or 382 strokers, bad and evil thoughts. I think if I get another 50bhp from the exhaust I should be fine keeping these evil ideas away for a while.

Not much

I can report that H0105 is all thats required to sort out Speedo issues noted in my previous post. I Logged a 80Km drive which clocked up only 50Miles on the Odometer.

Ive gone back to stock injectors offsets due to running to rich on low map zero throttle points. In an attempt to kill the richness off I set DFCO to go hardcore on me. Anything under 2% throttle at all map and rpm points. Works ok, but just when it disconnects hitting idle or low RPM to prevent zero fuel stalling you get a jerk. I dont mind too much, but I might readjust this nearer to stock.

I tested Alpha-n fueling, it worked nicely. Very responsive, but AFR didnt track commanded very accurately, it was close. However the feeling it gave was nice and responsive, so I will likely continue with testing.

Diversions

My Speedo has been dead for a month or so. No speed reading, no odometer and no trip computer. A post on ls1.com.au and thanks to motomk I had a wiring diagram and some disassembly instructions. Cool.
I knew the VSS sensor was working as efilive was logging road speed fine, so the problem was somewhere after the pcm. I also knew the speedo needle did work, because going into diagnostic mode the needle would wind up to 80 no problem. From the wiring diagrams I could see that the road speed signal also went to the cruise control system just prior to hitting the instrument display. Ok, so I tested the cruise control and guess what. It worked. I now knew the issue was between there and the speedo.
It was then that I recalled someone posting up an issue with UK spec HSV's basically an aftermarket device was fitted to convert the signal to miles from kilometers and it had problems.
A quick search on pistonheads.com and good old Steve had posted up some info from his VTSS. He had removed the device and resoldered it.
Now I knew what I must do.
Armed with this information I set about pulling the dash apart. First problem, no stereo removal keys. No problem, just bend the stereo bracket to clear the console!

All disassembled and instruments removed. Now where is that evil device!
Aha, here it is.

Now going into here is a red and black wire. Steve assumed power and ground. Id agree as it comes from a different section of wiring, likely needed to power satans spawn. Out of the device came an orange and green wires. Now thanks to motomk, I knew the wire from the PCM for the speedo was Violet/White, I could see that Violet/Red was cut and rejoined with a short piece of blue wire, no junction just cut. I can only assume the pleb who's job it was to fit these things cut the wrong wire first and had to fix it. So anyway I could see Violet/White was spliced to green which went into the device and orange was spliced into Violet/White up to the instrument connector. Up to this point my intention was to solder up the device to fix any dodgy dry joints and reassemble. However why not just remove it alltogether!? I knew I could use PCM table H0105 to correct the speed signal coming from the PCM, so Id save messing about, increase reliability and gain about a billionth of a second over the 1/4 mile due to the weight reduction, so I thought Id leave it out.

Here is what Satan's spawn looks like up close and personal. The capacitor next to the incoming wires was broken loose and just wobbled around. If you wanted to fix it, then this would be the repair you needed to do.

So I just reconnected the Violet/White wire together and taped the whole lot back up. Job done.

Take it for a test drive. Now reading Km, but not for long. By the way, I dont recommend test driving with just the instruments and not plugging in the power windows, indicators etc when its 28*C outside, it gets kind of hot.
The only thing Im not sure of is how the Odometer will read if I just rely on changing the PCM output signal. Im hoping that given its only one wire that was being messed with and it seemed to handle the odometer as well as trip computer and speed needle, then I will be fine. Worse case Ill have to pull out the dash again and wire Satan's spawn back in place. Ill update in a few days to report what the deal is.

On a more PCM based note. Im now running EFILive custom OS5. It works fine and takes OS3 calibrations. Basically it extends OS3 by adding switchable timing and fueling for NOS applications. You could also use it to pull timing based on a switch for fuel octane variances.

It also supports Alpha-n fueling which is purely determined by Throttle and RPM, no other inputs such as MAF or MAP etc are used. Its really designed for hellish cams that wont hold or give a vacuum or stable airflow reading. (I wish that was me!)

So Ill be likely making some comments on that in the future given thats now my PCM OS d'jour. So its goodbye to OS3 and hello to OS5.

More idle thoughts

It seems that the question of a smooth idle comes up more than almost any other question when tuning. Especially with aftermarket camshafts etc.
I guess when cruising in closed loop with the MAF just about anything will work. This is due to how closed loop feedback from the O2 sensors and the Mass AirFlow meter work. It really takes the guesswork out of tuning. No doubt exactly why GM use it.
Well throw a cam in there and when starting cold the car will be in open loop and at low rpm speed density airflow calculations come into play.
That sorts out those with good tunes from those that just do the easy stuff.

Anyway following on from those thoughts, Ive done a load of changes recently which threw my tune out. Just spent the morning dialing it back in. Now its nice again. (For the next day anyway)

Take a look at this first image, it shows the idle hunting up and down, spark, vacuum, rpm and if it was shown, IAC counts basically wavering to and fro. If it gets bad enough it will stall. Sometimes the oscilations will increase and get worse. Often when AC is turned on or the Radiator fans startup.


So all in all, it idles, but its horrible. Ok so how do we normally fix this? First we go back to basics and make sure that the engine is getting enough air at idle, or at least getting what it wants. To do this we log both short and long term idle corrections to airflow. These corrections are made by the PCM to try and get a stable idle. In efilive they are known as calculated pid's as they are summed and made into a single value for easy logging. So we make a map with ECT vs the RAFIG pid (Only this is needed for M6 cars, Auto's use RAFPN as well) as the car heats up it will log a map of adjustments required to the Desired Airflow table. Once warmed up, we shutdown and update this table. If you cant get your car to idle initally, you might need to start logging to figure out which way its going and just guess to get it to run long enough to map the adjustments.

So once the airflow is updated. Its worth going into the bidirectional controls utility to see if adjusting the spark and fuel mix would help the idle. In my case fuel was ok (set to 15:1 at idle) but spark was now quite a bit out. Dropping it from around 38 degrees to 28 degree's sorted out a lot of the hunting. Im assuming the new injectors and injector offset tables I have been messing with caused some of this. So easy done, all fixed. Now back to a smooth idle. I just made sure my high octane table and base spark tables were close in the idle and off idle areas, so that transitions were smooth between both tables and all is well. The resulant logs are shown below. Notice RPM is now almost dead flat and there is some slight adjustment to spark by the PCM to hold it there.

So there we go. A short run down on tuning idle for anyone who is having issues in this area.

Radiant

Well today was a mixed bag of events, a badly secured clip that held the IAT sensor in the intake came off and meant that the sensor dropped on the drive belt stripping a few cords off it and causing it to drop off. All this about 70 miles outside of London. I didnt have any tools so ended up with the recovery guy putting what was left of the belt back on.
I couldnt find the metal clip which had secured the IAT inside the air intake so thought Id just check where it went.. Yep, it was lodged at the back of the manifold near cylinders 7 & 8. The guy hooked it out with a magnet and all was well.

Suffice to say metal clips arnt going back in there. The rubber gromit the intake had come with was a bad fit so I need to sort something reliable out.

So that cancelled my trip as I didnt want to get stranded in Wales and have to leave my car there if I couldnt get a replacement belt, so back home I went. I managed to get a new belt and fitted that right away.

At this point things got better as I decided that I would then fit my new injectors and thermostat.

I didnt have a fuel rail removal tool, which is pretty essential to get them off so just followed some info on www.ls1howto.com, pulling the fuel pump relay cranking the engine to dump the line pressure then removing it. Suffice to say even though there was no pressure there is still a lot of fuel in there and you will get it everywhere, so make sure you have a rag.

Pulling the old injectors out of the manifold is easy, but they are well stuck in the fuel rail. All of them took a bit of effort to pull out and left their rubber seals in the rail. Once removed the new ones went in nicely with a little bit of petrolium jelly. Here is a pick from halfway though.

Note the IAT and MAF sensor connectors are now tied away with tape too after the earlier mornings troubles!

Next was the 160*F thermostat. All in, both jobs only took a couple of hours. I set the fans to come on around 80*C and the high speed fans around 87*C. To celebrate I also pushed timing up 3% across the board.

So a flash of the changes, including rescaling the injectors with RedHardSupra's injector table and I was away. Immediately I noticed VE was up to 10% out. Cool I thought, it did need more timing. I added around 5%, but then remembered some comments on Injector Offset. Basically the larger injectors are lazier at low duty so need more time to open etc. Joe who posts on efilive had posted some new tables which had worked well for him so I have used that as a starting point and will do some more logging and check to make sure that all that extra fuel is required. Hopefully it is and the consequence is more power. Knock is not appreciably increased over what it was before, that is, a tick now and again but no sustained knock under load. Only really there on throttle tip in.

So only exahust upgrade to go, some final tuning and off to the dyno. Also time for a few gtech runs I think.

Refinement

Got my 160* 'stat today and SVO's
Also playing about with Base Spark and High Octane tables. I think Im getting a little jerkyness due to low throttle positions swapping between both tables. Especially when hardly touching throttle. I have made both tables a little closer in value to see how that goes. Its possible its DFCO messing with things too, though often the RPM value appears below the DFCO enable point.

So a long trip tomorrow, then sunday, thermostat installation day. I think Ill take the spark plugs out too and clear off the corners as recommended by Vizard. Im hoping to be able to push spark up by around 10% across the board. We will see. I have 21 at WOT and 19.5 at Peak Torque which is very similar to my stock tune, so I guess thats not too bad. KR is almost non existent. As I think I mentioned earlier these heads will need less timing anyway. So maybe 22-24 deg is optimal.

I need to sort out the exhaust gaskets as Im getting some cat bypass pipes done up and they need the gasket to make the flanges up. I think Ill go 2.5->3.5->2.5 so that the 3.5 section acts as a resonator and terminates the collector length. Otherwise it will be 2.5 from the headers way back to the current resonators, which from my reading appears too far. Though Ill have to measure up to be sure.

So the current series of mods is coming to an end. Soon it will be time to go and see whats up on the Dyno.

Exhausting

After removing most restrictions with the new heads, cam, intake system etc I have now turned my sights on the exhaust system.

I spend some time with a tape measure and clamp measuring the diameter of the various parts of the exhaust system.

Well its not too good. The cat back looks ok, 2.5". The headers are ok, ending up in try-y configuration with a 2.5" exit. The problem then is the 2" pipe into the cats with the O2 sensor in there too! Thats less than 3.14" sq area compared to the rest at 4.9" sq for the 2.5" section. It will even be less due to the O2 sensor in there. Now if I knew what I was doing with calculating exahust flow Id be able to verify that the exahust is a restriction. Though I have read another Vizard article which states dual 2.5" exahust will support up to 500bhp without restriction. So based on my hope to be at around that level at the flywheel the exhaust is going to be a restriction with its 2" bit, so out it goes.

My options are to replace the cat system with a bypass pipe for "off road use". This will allow me to replace it for "road use" and emissions testing. Hopefully I dont forget to replace it and just leave the offroad pipes on :)

As per usual good old Mr Vizard has an excellent article on exhaust selection and design here.

From what I understand the main summary is that exhaust tuning can produce up to 500% increase in cylinder scavanging over what the usual induction stroke of the 4 stroke cycle produces. Primary header length is not as important as collector length, and wise placement of open chamber or resonator boxes helps to terminate the effective collector length. A good rule of thumb is 2.2cfm of exhaust flow per engine bhp. So a 500bhp engine requires 1000cfm of exhaust. In addition a 1"sq pipe flows around 115cfm. So from this I can see my 2"sq pipe will only flow around 350cfm, or a total of 700cfm (2 pipes) a 50% increase in exahust flow is required to remove the current restriction! And worse because both 2" pipes have an O2 sensor blocking half of it off!

So anyway looking at options now, which include replacement headers as well. I think this is going to have to be the end of the purchasing mission. Finances have taken a hammering recently so hopefully there will be no mechanical restrictions, or at least only minor ones. (Like not having a Fast90/90 setup!) Still waiting for the thermostat and injectors. Im pretty sure the 30lb SVO's will be ok as Im not at 100% duty with the 28's yet. Unless the replacement exhaust makes this change a lot then I should be fine. RedHotSupra has recommended 42lb injectors as they will fit more nicely at the 80% level. In retrospect this is likely to be correct. However the 30lb ones should be ok, but will sit at a higher level.

Still aiming at 400rwhp

Yay my first planned mod has finally arrived

Super cool awsome. My otrcai has arrived. Can you notice it in this photo?

It was made white for me by efi dynamics in Melbourne Oz. Thanks to Les also from ls1-australia for organising it for me. I chose white so it reflected the heat as much as possible. I might even put some silver reflective tape on the bottom. Might help it resist heat soak a little. Should be worth an extra 50bhp, what do you think!? Ok well maybe 0.1bhp anyway.

I had to take a sliver off the neck so it fitted back far enough for the bonnet to close. Nice and snug, so its not going anywhere. Did a test drive up the road. Definately makes more power. Some good sideways action at the round about to check and back home. I have a reasonable drive coming up thursday and an even longer one at the weekend so Ill get some good logging done.

Well new injectors 30lb Ford SVO's (yes I said Ford) are shipped. They should give me plenty of head room and are accepted as a good choice for heads and cam vehicles that need a little more injector capacity. Stock 26lb ones are only good for stock engines. The later 28.8lb ones are ok with mild cam only. But I logged a 92% duty the other day and that was still under 6000rpm so definately need more. The Ford ones rate around 36lb on the GM pumps due to higher pressure, this should be good for around 650bhp based on my understanding of BSFC, which admitedly is probably pretty shocking.

BSFC as I understand is the engines ability to turn fuel into power. A more efficient engine will get more power from each lb of fuel. Forced induction engines are good, as are some high compression NA engines. Take a look here for Mr Wikipedia's take on the matter.

Ok so now I shouldnt be intake restricted any more. Thermostat will help keep engine and combustion temps under control so I can get a little more timing.

I did a traction limited 0-100 of 5.6sec the other night. Not so brilliant. But that was my first go. I will run a few more times and practice my launch etc. I think I might be able to get it to very low 5's and will some luck and probably more tuning even under 5!

Also today I messed with a number of tuning tables in order to arrest my reverse full lock low speed stall. It appears totally fixed now. Cool. I might celebrate by dropping idle down a little to 780 from 800 and see how it goes. It will idle at 700 rpm, but is a little tetchy about doing so. I think 780 might be good enough.

I thought so

A day spent on and under the car again today.
Some new NGK-BKR6E-11 plugs, well cheap I think about £12 all up shipped to my door. They are shorter than the stock Autolite plugs so will create less compression and run cooler. I pushed timing 0.5 degree up to celebrate and no KR was logged so things are heading the right way. Cold air intake and Thermostat to come.

I also ported my throttle body today. Here is the pic, a little blurry, but there you go.
An excellent writeup here on how to do this. I cancelled the BBK one I ordered, everyone says there is no point upgrading unless you go for a Fast90/90 setup.


Also here is a pic of the old plugs I pulled out. Ive done some spark plug research and Im guessing they looked a little lean/hot. But within acceptable limits. Take a look here for an excellent link on spark plug reading. New plugs are gasketed, which is the recommended plug for the darts. So plugs are now as they should be. The old ones have been consigned to the spares basket.

I also found a small exhaust leak, which was the likely reason my girlfriend was complaining the car was making her sick, "worse than before". And there I was thinking it was my driving all along, or the increased power and whiplash etc.

So good progress, slight increase in power and hopefully more to come with the remaining parts.

If you havnt done so already PORT YOUR THROTTLE BODY! Its easy and rewarding.

Last fuel fill the distance remaining read 420 Miles, which is pretty good, same as prior to heads and cam upgrade. So there you go a nice small port high flowing head with good compression and a mid-ish size cam can get you good street manners, more speed/power and retained economy.

Just a little by the way. The Dart heads have about 0.100 less valve clearance over stock heads. So notching pistons is more likely with the Darts. The valve springs are good to 0.620 but the drop wont support that with out compatible pistons.

Another learning experience

Ok, so in hindsight (which is often the way these things get found out) Id have been better with a slightly lower compression setup. Im still confident that I can make do with my current setup with the mods mentioned above, but Im right on the edge. Timing is such that knock is not an issue. Its just not ideal for power.

So today I ordered the 160deg thermostat from Summit. In addition some serious WOT action today showed that my new slightly higher rated injectors wernt going to cut it as they were running 97% duty. With the new intake and hopefully additional timing which should require a little more fuel to get back to commanded fuel ratios Ill require some extra headroom. Actually the recommended headroom is to aim for 80% duty cycle anyway. Stock early LS1's are almost at 100% off the showroom floor! Anyway the reason I mention this is that I got some Ford SVO 30lb injectors. They will work out at around 36lb with the GM 4bar fuel pump and give lots of headroom.

I thought seeing as I was at it I might as well order a BBK 80mm throttlebody as well. The budget is now seriously blown and expenditure needs to be trimmed right back as things are getting out of control. Hopefully I can restrain myself and not buy a new exhaust system. The current one is ok, twin 2.5" but has cats and 2 mufflers on it. I need to pass emissions and see what my margin for error is. Hopefully it may allow the removal of the cats and while Im at it one of the mufflers. That might help airflow through the engine as well. Im currently running 0.85g/cyl which is about 0.07g/cyl off what Id expect (0.92g/cyl) Im hoping timing, throttlebody and cai will get me closer.

Timing and Octane

Well the past few days have been interesting.
I managed to fill up with 100 octane in Germany where its cheaper than 95 octane in the UK.
This allowed timing to be increased 3 deg with what seemed like a small increase in power.

I had been wondering why, if lower timing was better, why not just run lower octane and lower timing. Well after some reading and investigations the answer appears that if you run too low with timing the combustion will still be happening when the piston has past its best position for combustion pressure. (Around 15deg ATDC) So the ideal octane and timing is the one which puts the most pressure around 15 adtc and is all spent before the exhaust valve opens.

From others comments and feedback this optimal timing appears to be around 24-28 deg, now there will be variables such as combustion chamber design of aftermarket heads etc which could move this a little one way or the other.

My timing with 95 octane was around 18 deg. With 98 Im back to around 20 deg. Im hoping with the changes detailed here to be able to creep towards 24 deg with no observed knock.

So Im now officially running 98 octane and am embarking down a track to optimise compression and timing settings. My compression with Dart heads is right on the line, so extra margin for error will be good and hopefully allow more power from optimised timing.

A quick read of this excellent FAQ will reveal more for those interested. Particularly section 7.

So in order to see how this goes I have just ordered a set of 8 x NGK BKR6E-11 plugs which are a gasketed equivalent to the TR6 plugs. They are standard copper. But if they work well Ill change to Iridium.

Anyway my quest for reliable compression and timing will be as follows;

• Fit OTRCAI cold air intake to reduce IAT temps (on its way, hopefully here in the next week or two)
• Fit lower temperature Thermostat 170*? (currently researching this, David Vizard has a nice article covering all this here)
• Fit colder spark plugs as mentioned above

Other changes such as combustion surface polishing etc are out of scope for the time being, as the engine is already assembled. I could also retard the cam and flycut the pistons (dual benefit of allowing more lift and dropping compression) but wont for the time being.

The maximum benefit looks like it will be realised by the use of a lower temperature thermostat. Here the idea is to reduce heat soak to the intake air and closely related to this, the combustion chamber pre ignition temperatures. Thus inhibiting the spontaneous combustion that goes with knock. See the chart below from the David Vizard Popular Hotrod link above. My DCR is 8.3 or close to, according to this calcuator here. (Use 3.91 for gasket diameter, 3.9 for bore, 3.62 for stroke, 6.1 for rod length, 0.055 for stock mls gasket on stock ls1)

So based on 98 octane (98 + 87)/2 = 92.5 I need to be looking at a 170* thermostat and regulate engine temps around there. Users of the popular 160* thermostats report general operating temps in the mid 170's so. I think a 160 might be the go. I can regulate things somewhat with fan operation. Just need to order the thermostat now...

Other than that, I spent a good few days logging and one lap of the Nurbergring. Which is situated in the nice little town of Nurgerg in SW Deutchland. I logged the lap, but sadly cronic understeer from shoddy worn cheap chinese tyres prevented to much speed. I will rearm with better tyres and schedule another visit. It was great fun. Next time Im going to book a lap in the BMW M5 Taxi that takes people around. Apparently the drivers are excellent and will do a very very fast lap including some good sideways action.

I also attended the F-Body meet in Meerbusch, a good crowd from throughout Northern Europe were in attendance. Mainly older 3rd gen's but a few LSx vehicles were around. I took the organiser for a blast with a few of his friends. He said power was very smooth and fast. Which reminds me, its soon time to redo my 0-60 times.

Clarity and chaos

Well, day 2 saw the horrific discovery that the reason why the WB02 wasnt working was that it wasnt plugged in!

Starting had been a problem so I swiped a cranking VE table from a modified tune on www.holdencrazy.com. Starting is now fairly good, a couple of turns and its away rather than protracted cranking and throttle use being required to get it started.

Once started things got real messy, the idle was hunting up and down pretty badly. I recalled some comments regarding idle spark control and an investigation of tables B5934 -> B5936 showed that up to 25 deg was being pulled on startup. This showed me where the 9 deg total timing was coming from. Once warm it settled down and spark was running what I had set it to in the base spark table. So some big chops to these tables were made, basically 50% off each overspeed table. Underspeed was left as is. This seemed to make a good difference as well as generally reducing the cracker values overall. I had dialed my desired airflow in fairly well on day 1 so just a small amount of extra air was required.

I should mention that my baseline tune was a 2004 HSV GTS converted to efilive custom OS3.

Low level VE cells needed to be reduced a little, nothing more than 5-10%. Some higher end cells have gone up by around 7%. Im going to compare with a tuned VE table shortly to see where the gains, if any are.

I still have some low speed coming to a stop issues and when fan and power steer load goes on it can stall. I will add some more air for the fans and look at cracker and follower for idle transition stalling at low speed. All in all its come a fair way so far.

Spark is fairly close to stock a little less in parts. Compression is a full point up and spark at idle needs to be around 8 deg more than stock cam. A few more weeks of tweaking and it will be off to the dyno.

I wish I could have got a larger cam, but this one has a very wide powerband, I seem not to have lost any low down power except the car will surge in 1st gear crawling along the road with no throttle, so I guess no surprise there. Basically exactly my requirements. I have to meet emissions standards so it was 224 or less sized cam. I chose 220 for a safety margin. The car pulls well into the 6000rpm range. Im guessing Ive added power over around 3500 rpm to redline. Not sure how much yet. Its not like night and day which is what I was expecting.

Mr Dyno will tell all.

Stage one... again

Cam bearings were just within spec. So cam is now in.
Strangely piston to valve clearance was not sufficient to use the higher ratio rockers. It cleared, but not by enough to allow for heat and wear. Others have been able to get larger 23x duration cams in without fly cutting the pistons however I did note that my 0.006 spec's are very close to the larger cam specs at that lift. Perhaps due to high and fast lift. I just checked against the F13 cam and the crane has a later IVC and more 0.006 duration. So I guess that answers that. It must have slow ramps.

Anyway, car would not idle initially, I gave it 20% more RAF (Desired Airflow), still not good, so 20% more and once slightly warm it idled ok. I did a half baked log to check for idle air, but had to keep the throttle open to get it to run without stalling. Once warm it was fine, so Ill have to relog when cold. Its likely even more air is required.

Inital idle spark was 9 deg for some reason. It should have been over 20, so I will need to log some more and see where it got the 9 from. I overrode the spark with the bidirectional controls and got an idle map of 38kpa with around 34 deg spark. The engine runs crap with 9 deg spark, no wonder it was stalling.

I think the shop must have pushed the WB02 recall button, you know, the one with the red LED that nobody should touch, while wondering what it does. So anyway no chance to do any VE tuning as you cant recal the WB02 until the car has sat for 8 hours or you unscrew the unit from the exhaust and recal in open air. Suffice to say Im waiting 8 hours as its windy and rainy at the moment.

I drove off with my idle kind of ok except for coming to a stop when if I turn in on the power steering the car cuts out. Might need some cracker action or possibly even more air as mentioned above.

Next issue is due to no view of AFR I logged NB02 voltage as a kind of rough view on things. It turned out I was running over 1V constanly at low MAP (ie) very rich. Miles to go was falling like seconds on a clock. I pulled over and made some adjustments until the voltage was visably moving around. I drove like this for a few miles to check that the O2's were still working ok then turned on semi open loop fueling in custom os3. Basically if you command 14.63:1 the O2 sensors will trim the fuel to stoich. If you command any other values O2 feedback is not used.

This worked much better allowing the car to run pretty well. The STFT values showed that the VE table was out as at idle they were -15% and at some points +10%. This will be sorted out when the wideband is working again.

I swapped in my old spark map as the GTS table was showing up too much KR. Maybe due to the increased compression ratio or 95 Octane fuel. Lots more experiementing needed with spark and fuel.

In fact VE is fairly easy to dial in when you have a working wideband. Idle will take me a bit longer and spark will take the longest. Ill have fine tune it in on the dyno.

Af far as how the beast goes now. Im not sure. It feels at least as good as it was before and slightly beefier in parts. Nothing major. But Ive kept out of enrichment so far and its in a pretty basic state of tune. Idle is quite sedate, nothing too hairy. If it wasnt for emissions compliance I think Id go for the popular 224/228 comp cams grind.

More info once fueling and spark is dialed in further.

Under the knife

Well the doc has my R8 under the knife. We discovered the cam bearings are showing signs of wear which seems to be quite common. So the bearings are being measured out to check for signs of uneven wear etc. Ive got my fingers crossed that they will be fine otherwise its an engine removal and extra ££ to sort them out.

Worse still Im booked on a ferry to Europe late may!

Hopefully all is well, we will see in a few days.

T minus 20

Finally all my parts are here. It took UPS 3 failed attempts to actually deliver on their delivery date. I was told 3x that the guy would be around, each time they never turned up. Suffice to say that the 3rd time, severe anger management was required. Luckily the local manager sorted it out and someone dropped them off. Still if I could be bothered Id chase them up for compo. I had to take 3 days off to sit at home. Perhaps I will write in and complain anyway.

Still that aside. The Dart 205cc heads are in. There is a little casting flash and the chambers arnt polished. But I dont think Ill get around to doing much with them. Id have to pull the valves off. Make sure they went back on the right ports and be careful of not damaging the seats. So for the extra bhp from removing the very minor flash, I think Ill leave them as is.

Car is booked for later in the month to get all the goodies installed. I have a trip to France to do before then. Pity I couldnt have it done before then.

So anyway back to tuning. Ive been helping a fellow LS1 owner sort out their tune. The o2 sensors were placed back pre cat as the previous tuner had put them post cat. Well what do you know, the car now passed fast idle test, which it used to fail with excess CO emissions. The guy was having fuel consumption issues so we dropped idle speed and advanced up the timing a little. It idled nicely at 650rpm. However perhaps because of this it failed the natural idle test. Again excess CO. I read somewhere that a nice hot engine and faster idle and strangely enough more retarded ignition should sort that out.

Im now wondering if thats why the OEM tunes run such low timing and high idle speeds. Not for fuel consumption, but for economy. Anyway Ive offered to return idle to stock so he can get the emissions checked out again. I think we might have it sorted if thats the case.

Otherwise Ive been playing with fuel octane and without changing any spark timing running a higher octane, 98 RON seems a little more peppy. I need to do another tank of regular 95 RON before I know for sure which is better. Mind you come the 11:1 Dart heads and I think I will have to use 98 RON anyway.

Id been having some issues with efilive OS3 where commanded fuel did not match acutal AFR. Basically the efilive guys had seen the issue before and the PCM was entering PE mode and not exiting from it. So AFR was at PE even when off the throttle. Anyway I decided to change more PE triggers and not just the MAP trigger. I set TPS to 100% for all RPM points as well as setting commanded PE AFR at 14.7:1. Since Im running a fully flexible AFR map as in my last post I should never need PE mode. So in theory I never went into PE, except that I was! Anyway it now seems like that little monster is sorted. Ill have to recheck a few more times to be sure as it was intermittent in any case.

When I said all my parts were in, I actually meant all my parts except my otrcai, which should really have been in months ago. I had comitted to one last year. Apparently its been ordered and is on its way. Still my brother lives in Oz, so getting him to mail me one shouldnt be a major issue if the one I have lined up falls through.

Hopefully my next post will be with all the parts installed and no issues to relay, except excess power and lack of traction.

For those looking at getting good power on a budget here is the basic run down.

Parts: (Prices in $US)

• LS6 intake and injectors, bought from ebay in OZ from MantaLS1 (Thanks dude) $175
• Crane Cam HR14400067 grind, same as Vinici cam and known as SDPC custom $310
• GM MLS OEM Head Gaskets
• GM OEM Head Bolts
• Dart 205cc LS1 Pro1 heads $1295
• GMPP LS1 Oil pump $69
• Rollmaster timing set $99
• Various gaskets for timing cover, pulley bolt etc $100

So total cost is about $2000US plus shocking shipping costs of around $1000US, but that includes horrendous UK VAT at 17.5%

Stock the engine was rated at 345bhp, Im hoping to see near on 500bhp on completion. I might need a new clutch and injectors, but Ill worry about that later.

The waiting game

Well, Ive been watching the grass grow for a while now. Those Dart heads dont seem to be getting any closer. Apparently they are backordered for weeks, selling like veritable hotcakes.

In the meantime, Ive taken the knife to my tune with economy in mind. Im still running open loop with no O2 feedback and Speed Density mode (MAF disabled/disconnected). Soon a new MAFless intake will be here too.

In the meantime I have done some changes to efi OS3 table B3647 as below with the idea being that stock lean cruise and fuel cut off do much the same thing. I have basically leaned out low load points. This is a table of commanded AFR vs RPM vs MAPThe car runs fine with no decernable loss of power.

In addition a few of the afterstart enrichment tables and values have been pared down.
I have taken around 25% off these to lean out startup. Commanded fuel when cranking, initial fuel prime etc. The car still fires up fine so Im going to hold off getting too radical on cutting this down until the new cam and heads are in. Again things still work fine, however hopefully Im now using less fuel.

I might be spending some time this weekend with a fellow Holden owner taking a look at his tune. Its running zero trims but runs rich on the exhaust analyser. As mentioned on a previous post, his O2's are located post cat. So I suspect changing switchpoints will also require changing the VE to take about 10% fuel out. Should be interesting in any case. Hopefully we can sort out the issue.

My brakes were well seized up. So after a visit to a workshop they are now running well. Ive not hammered on them yet. Too much stuff all over the place in London. Looking forward to the cam install. It cant happen soon enough!

Oh one more thing. I read an article which stated MBT was around 3-5 degrees from knock point. I'm not sure what engine that was in, but it was good to get a fairly definate indication for the best timing.

Daniel at Chipmaster in Oz has a nice little page on tuning up here too.

Return to darkness

Well after an eventfull holiday with no less than 3 tickets in NZ. This included a shocking display of NZ Police incompetence with me being told I was banned for driving in NZ because my NZ license had expired years ago and that my UK license and Passport were not acceptable, despite the so called officer telling me that visitors had the right to drive for up to a year on their UK licence. Needless to say I ignored his pointless and childish grandstanding.

Oh, the other tickets were for speeding. One for 114Km on SH8 with a 100Kmph limit. Also fairly pointless on what must be one of the worlds least busy roads. The other was 127Kmph. Lesson learnt was to not watch the road and other traffic and instead watch the speedo and ignore all external events and road conditions.

Aside from that the 28 deg C weather has been replaced by sunny London's sub zero overnight temps, dark rainy days and 5 deg C daytime temps. Nice.

I had time yesterday to roll under the car and get dirty replacing the shifter with a Rip Shifter. The front bolts are a nightmare, but once the trans is lowered a little its actually quite simple. Shifts are shorter and more direct, much nicer, though I think I preferred my B&M Shifter in my camaro for shorter shifts... and cost. Total time for install was 4hrs. But you could take 1hr off I think as I messed about from the top with the tricky bolts rather than just dropping the trans as per the instuctions right off the bat. Another lesson learnt :)

I have some NZ pics showing the Commodore and some nice scenery. For those who like V8's, open roads and scenery, I recommend NZ. The west coast is nice and windy and lots of fun can be had without exceeding the speed limit (to a certain extent).

A fellow UK owner dropped by yesterday to get me to do some scanning. His tune was running rich and dispite all new parts failed emissions testing on a stock engine! Obviously something was wrong. We took a look at the tune and while LTFT was pretty much at zero there were a few weird things.

O2 switch points were all set over 500mv, in addition the sensors are apparently located POST CAT, which would cause them to read leaner anyway and dump more fuel in. His VE table was around 10% more than any other stock engine tune Ive seen at low RPM. I think he needs to change his switchpoints and get the sensors back into the right place before the cats, preferably in the collectors. I need to ask him if his headers have sensor bungs. Most do.

Alternately we can run open loop, but this really needs a wideband to check how things are going given his O2's will give us even less useful info than they normally do. So a few interesting points to look at. I think he will make some more changes to crack the issue.

Encore un fois

Ok, so Im sitting in NZ at the moment after tuning my friends SS Commodore. Good results, though he has stock exhaust manifolds and MAF. The tune was mafless and based on the R8 tune. I had to pull some timing from 4500-5500 RPM to prevent real knock. Though the rest of the table is pretty much stock R8 285KW.

Quite pleased with the results, I think he will get an OTRCAI to minimise intake temps as they have a considerable effect over 30deg C with quite a bit of timing being pulled.

I used a combo of efilive OS3 with open and closed loop. Low map was open loop leaned to 15.4:1 AFR, while midrange was closed loop and WOT open loop as normal. MAF codes disabled and MAF disconnected.

Took 13 revisions to get it to where Im happy with it. Some of these were on/off settings to try one then the other and back again. Compared to my over 130 tunes, 13 for his isnt bad. I kept a little conservative, though he asked me to sharpen it at the end so he had max power. There is still no knock showing, though Ive seen him drive and its not pretty, WOT from idle in all gears!

Anyway, thats my second tune so far. Ive decided that for mechanical and volumetric efficiency reasons I must purchase a set of Dart LS1 Pro 1 heads of 205cc capacity. That should give me 10.75:1 compression with good flow rates. Ill order these as soon as I get back to the UK.

Im still waiting on an OTRCAI, there are none in NZ, or at least none I can find. Im looking at the Orssom range from Charlie in Oz. A new batch are due any day.

Timing revisited

Ok after much hair pulling trying to remove all trace of knock from all logs, I had found I was going around in circles. No matter what timing was there would always be some logged knock.

After some discussions with fellow tuners the consensus appears to be that as mentioned previously, real knock you should worry about is "saw tooth" in shape, while incidental and false knock is just a small spike which will show now and again. Or in other words "false positives". Just like an anti-spam engine will block good emails on occasion, the knock sensors will log random nothings from time to time. However big spikes and saw tooth shapes suggest real knock so be wary and careful not to take this post as a recommendation to allow real knock to exist at all.

So in summary Im pretty much back at my timing table I ran for the dyno pull happy with the fact that the odd tick on the log now and again is acceptable. With this in mind Im warming up to an OTRCAI purchase to go with the cam and possibly some Dart 205 or 225 heads.

Sparky

As time progresses my right foot seems to fall heavier on the throttle putting me into load areas previously not dwelt on for too long before. Ive pulled some more timing out and am now sitting on around 20deg total at WOT, part throttle timing has also fallen. Interestingly enough power is much the same. This reinforces the often read and heard line that "best timing is miles away from knock". The idea being that you should run the minimum timing you can to attain peak torque. This point is known as MBT (Minimum best timing) afterall burning the charge before TDC means you are fighting the compression stroke. To set timing at minimum buys you some safetly for dodgy fuel and conditions.

As mentioned previously this is ideally setup on a load dyno. I tried to get some 0-60 times on myGTech the other night as a kind of "check" for my tuning changes, alas, it appears that it may have completed its life on earth as it was spewing out non intelligable figures not related to the mode I was in. Ill try it again and have another go, else its time for an upgrade to the GTech-R version which does torque graphs. Perhaps you are wondering if I may have hastened its demise? Ill leave that question unanswered.

Very shortly I shall have in my posession the following items;

• LS6 Intake
• 28lb injectors
• OTRCAI
• Short throw shifter

These plus my 220/224 cam = more tuning fun.
I have tentatively booked in late Feb for the cam and other parts install. Though Ill put the shifter in myself beforehand.

Idle thoughts..

Firstly a clarification of an earlier post on KR. Tordne brought to my attention the fact that I mentioned voltages fluctuations can indicate false knock etc. More correctly this is fluctuations in the recorded KR, which does relate to voltages obviously, but the item to log and observe is the KR in degrees, not a voltage reading. I dont want to edit previous posts except for grammar as I think it shows the learning process more clearly where there is slightly confusing statements, but thought this was worth mentioning anyway.

Ok so after more reading and yesterdays trials I think I now have a good understanding of Throttle Follower and Cracker settings and they actually have nothing to do with idle! They are for transitioning to and from idle.

A lot of the idle tables are inter-related and some effects that appear similar can be down to other tables, here are my current thoughts on 2 off the idle transition tables.

If you have an issue when coasting and going into neutral where rpm rises I think this will be a Cracker issue, you need to reduce the cells where the problem occurs.

The Follower is for leading into and out of throttle transitions so rpm's ramp in and out rather than hammering in and out. (Perhaps to prevent wear on the driveline!?)

The desired airflow (RAF in HPTuners) and IAC Parked Airflow tables are the ones to give you a smooth parked idle from cold to warm.

So if your vehicle bogs off the line, you should look at the Follower values, if it rasies or drops rpms coming to a stop its likely the Cracker tables (during shifts also consider the Follower as it decays airflow on throttle reductions).

If you put too much Follower in you might need to reduce the Cracker accordingly.

Also as per my previous post if you want more off idle throttle response take a look at the Follower tables (The the added airflow and multiplier ones)

.. Ok so I got bored

While planning the next set of changes I decided to try and chase down some minor idle issues. Like RPM dipping at low speed when in neutral.
After some reading on EFILIVE forums for idle transition and idle tuning I made a few maps and pids and went logging from startup to full operating temp.
I pasted the changes into the Desired Air Flow tables and things are now much smoother. I think the 1.8 rockers might have thrown the stock idle table out a little. Good stuff, Im now prepared for some cam idle tuning next year come cam install time.

That was too easy, so I decided to look further into suggestions that you can get a similar effect to a "pump shot" by messing with the throttle follower tables. This handles the transition from idle to running airflow. Factory default is to trickle changes in until throttle position sensor (TPS) is at 13% at which time it is increased 6 fold! There will be some interpolation, but I decided to make it more linear, so scaled the roll in from 3% TPS and set the mulitplier at 1200 to match 1600 RPM lead in. The car now launches off much more confidently without the delay from idle requiring 15%+ TPS to make it do anything. Another sucessful series of tuning actions and no observable ill effects.

I will be logging a lot come tuesday as Im off up North again so will check to see if this additional airflow has affected my AFR readings and hence VE table. I doubt it, as its only put in on TPS +ve delta changes, then decayed out.

Stage one complete

I decided that my tune was close enough to warrant a trip to the dyno to check WOT fueling, timing and power.

The guy was very helpful and didnt mind me digging my laptop out and hooking myself up. On his advise Im now at 12.5:1 at max torque, which gained me 3bhp and 2ft/lb over my tune.

I basically overloaded their dyno as you can see my power run is cut short. I will try somewhere with a beefier dyno next time. I think I can make up more power with my LS6 intake and a new otrcai (Over the Radiator Cold Air Intake), plus run some high 98 octane fuel. Im also running cats still. Anyway peak power is normally aroung 5500rpm my run was cut short under 5200rpm so I wont know till the next time where we are at. Indicated flywheel power is 362bhp with 364ft/lb this is because the dyno measures trans loss on the overrun, apparently pretty accurate.

So I think for now Ive got things about as good as Im going to get them unless I retune for 98 octane. I think Ill just leave things be until March when the cam, intake and injectors all get changed then retune for 98 octane too. Im hoping for at least another 50-75bhp. Apparently the LS6 intake is worth 20bhp itself, plus maybe 10 for the fuel and 40-50 for the cam. We will see.

Injector duty was at 92% on the dyno so the new injectors will be required.

Tordne seemed impressed enough to request my tune and go looking for an HSV285KW base tune too. I had based my timing on the HSV table and found it very good. This was the last HSV LS1 engine before they went to the LS2 so I think its got a lot of good things in it to make good power. Basically 65KW over the original 220KW LS1 engines from 1999, which is a 30% increase!

Here is the cut off table with my tune overlayed on the tune as recommended by the dyno dude. (Just change fuel from 12.6:1 to 12.5:1 at max torque)


So thats it for now. No more updates till I get some 0-60 or 1/4 mile times... or I get my extra goodies on.

The cracked nut

Ok things seem to be going pretty well now.

I have totally axed PE mode as I was getting a "bog" when throttle went past its trigger position and enrichment started often at too low rev's. Now it comes on progressively after 85kpa richening up at max torque. Delco recommended a trigger of 80kpa rather than the factory 15kpa, but with the custom OS thats not required as I can command it with table B3647.

Ive been reading lots. Too much advance isnt good. In fact less advance in theory is good depending on what the power output is and at what point of the cycle it occurs. Afterall if you can spark after TDC on the power stroke and have max force expended on the downwards stroke then you are not wasting combustion pressures on slowing down the compression of the charge.

Here is my current spark table as of today.


So in summary its not important to get hung up on how much advance you can run. Your engine will be tuned to its fuel based on many aspects including its VE, combustion chamber design etc. Im running 22.5 deg at max torque around 4000rpm. It wont take any more without KR. In fact it might run even harder with a little less advance. What I did notice however is that after adding a few degrees at the lower end things have got very lively in the low and mid ranges, so much so that I requred a full 5% more VE across the board. I did take some timing off the upper end and some minor VE adjustments, however the engine is now running well.

Previously through the 70+ tunes that its now had in it I could pick out times when certain area's and parts ran well. Now I cant detect any part which needs improvement. Well not quite true. Id like a little more straight off idle..

I may richen up to 12.6:1 at WOT peak torque as Im running 12.8:1 and some recent reading suggests I should go a little richer and lean it to 13.1:1 above and below this point. Though near the redline and fuel cutout, I think a lean towards the high 12's would be more prudent there.
I dont think timing could be improved much more, subject to a dyno tune.

I must get some 0-60 times to see where I am now. In fact no more posts till I have done so :)

Book fest

Just got my book by Jeff Hartman, basically an MIT text book for Advanced Mechanic students. If you like differential calculus you will love this book. Its a nice 600 page tomb.

Lucky the book uses the maths to demonstrate the text, though at times I think it just gives up and explains things with long physics formula. Anyway very interesting so far. That will keep me busy over the holidays.

Anyway, my tune continues to improve. Im not convinced with "Lean Cruise" and have reduced the factory lean out by 50% as I had to put my foot down quite a bit to get it to maintain cruise speed. This was backed up by some comments from Delco at chipmaster in oz, an amazingly helpful pro tuner who seems to live and breathe GM PCM's. I understand he wrote some of the code for EFIlive.

Ive left DFCO on as I like the engine braking it creates. I also wiped out PE mode by setting map to 110kpa. I will use table B3647 to command enrichment instead and see how that goes. The main reason for this was that PE came in at 64% Throttle and I could feel the engine slump at this point. I was assuming that it was PE cutting in. Either that or the richer fuel.. or maybe lower spark advance. Anyway stage 1 test is to see if turning TPS and PE off makes a difference. If not Ill look at the enrichment settings. Basically 13:1 going to 12.8 at max torque then back to 13:1.

My commanded fuel is more gradual, though ramps to the same settings.

So Im summary my low end and mid range feels great. Im not so happy with the higher RPM range and believe it to be either PE or spark that is the cause. I got a little KR around 0.60g/cyl and 4000rpm, so have pulled timing there down to around 26deg.

More updates once I see how the recent changes go.

Im starting to read up on idle tuning in anticipation for some tuning action when the new cam comes in.

Nice

Still lots to learn, but a few things are starting to fall into place now.
My new (well HSV derrived) spark table was fine, no knock retard at all, so I merged a little more hardcore Corvette table in. I got a tiny bit of knock, but only at 4000, that was with some WOT runs, so that was cool, basically at Max Torque, where apparently its good to run more fuel. Fuel at that point should be sitting at about 12.8, maybe I should drop it to 12.5.

There is a discussion on efi101.com forum about more timing and more fuel vs less timing and less fuel, the consensus for performance appears to be that slightly leaner with less timing is good. So Ill pull some timing for now and see how we go.

Just as a reminder of how far Ive come I found this henous old VE error lable, using LTFT readings. I guess its not a million miles out, but its certainly all over the place. Rich down low and lean up high. I think if I have smoothed it out heavily and worked on it, it would have come right... Which in fact it did with some assistance.


I was commanding 14.63 and STFT was trimming nicely yesterday but as I have my LC-1 in as NB02 the signal isnt quite 100% the same, it tracks closely, but in the end one bank was reading like 6% different than the other. I thought this might not be good as they might be fighting against each other especially if the LC-1 was switching at the wrong point. So Im back to a non commanded 14.7 running soley off the VE table. Now getting that to track acutal is much more of a challenge. STFT were running an average of 2% out, so things arnt that far out. Each time I adjust 1% it swings the other way, so I think I might mess with IAT modifier or something else other than the VE table.

The car runs like a psycho now, light throttle causes nice acceleration which starts peaking a little over 4000rpm, it still pulls to the red line, but its not really worth it as the fun is done. My new cam Im sure will address this minor issue. Then the tune can start all over again!

So now Ive just got a little more playing around with the timing then most things will be right on. I dropped my idle to 625 the stock HSV is 640, so the timing must speed up low rpm operations and allow a much reduced idle. Tordne's idle was 900, so I suspect he can find more power in his spark table. He has said as much as he is now running a modified Corvette table.

The joys of not having a dyno to create a properly mapped spark table. Perhaps once I get the cam in I will pay for some dyno time to dial in a good spark map.

Back to basics

I have an excellent book by Jeff Hartman on fuel injection. It has some very good information and after a fair few pages I understand a lot more and am feeling ready to start messing about some more.

Tordne had shown me what a good VE table can do though in the back of my mind I had thought that one of my previous tunes had felt "sharper" down in the low RPM range. Tordne has mentioned that he has started experimenting with a late model Corvette spark map. Aha, cool. maybe I was right afterall. Time to dig out that aggressive HSV 285KW map I played with earlier and try it again now I had updated Knock settings.

Im going to also configure a VE modifier for IAT temps. This is due to a large variance in AFR over a 10-40 deg C temperature range. Im also keen to switch DFCO and Lean Cruise back on to maximise long distance driving efficiency. The cam is burning a hole in its box waiting to get out, unfortunately there can be no rushing things there as I need to get my new LS6 intake over from NZ as it will be going on the same time as the 28lb '03 injectors and cam. Im hoping for about 380RWHP, we will see, that might be somewhat optimistic, but certainly within the realms of possibility.

In cruise mode

Ok, so not much of an update today. Basically we have done a few tweaks to various parts. Tordne has suggested retaining PE mode in addition to table B3647 as both have their pro's and con's.

Id like to reenable DFCO and Lean Cruise shortly. Though that throws a few spanners in the works if you still want to tweak your VE table. I also thought that using B3647 to run semi closed loop, where it will use Short Term Fuel Trims (STFT's) to maintain AFR at 14.63 would be a good idea. Though Tordne made a point that if everything is 100% correct you wont need STFT as nothing will need correcting. So yes, I think things are pretty close. The main reason Id like to make a "final" tune is so that I can get the laptop and cables out of the car and go for a proper drive. Having laptops balancing on the seat with cables everywhere does not make for a spirited drive.

Of course closed loop may still not result in a commanded 14.63:1 AFR as the O2 sensors are not in their stock location. Others have resorted to altering the O2 switch points in order to bring these back in line. I think mine are stock HSV R8 which Im not sure have headers from the factory. Anyway the best way to check is to operate in closed loop and check the AFR. Mind you Ill be using the WB02 to output NB02 signal to the PCM, so the LC-1 will be measuring itself. It will also only be measuring one bank of cylanders so thats not the best in any case.

I bought a Fuel Injection book from a US company for $8US so will do some reading there. Maybe some more revelations will surface.

Only 2,000,000 miles to go..

Well, after discussing some issues with a co-tuner Tordne around various things like VE variations around Intake Air Temperatures (IAT) etc, I think he felt pained by my slow progress. So a short drive later on a baseline tune of his, he sent me a new baseline for my setup. Interestingly enough my VE table was 10% higher than his up to around 3600RPM. This may be due to a number of things, my LS1 intake, IAT being aroudn 10deg C here (his was 40) and my 1.8 rockers. I think its mainly the rockers and LS1, apparently the LS1 intake actually flows better than the LS6 at the lower end.
Here was my VE beforehand.

The sunken bit is where its dialed in ok, the rest was due to the intial "15% scale" recommended by efilive for autotuning. Tordne made a good point that sharp variances are averaged by the PCM so can cause some erratic results. His tables are very nice and smooth. This is reflected in the tune while driving. In a previous tune I did hammer the table flat with the smooth function, but hadnt got around to it on the new one yet. So thanks to Tordne, I now have a nice smooth VE table as a base. Ive got 2 long drives ahead of me, hopefully I can get some good results from them. It looks like Ill need to use table A00014 in the custom OS to adjust for IAT over the seasons. Anyway here is Tordne's work of art. Can you tell any difference?

So yes, summary for today is that smoothness is good. Maybe Ill show you the spark table next. Ill save that for my next update.

The road well travelled

Ok some major advancements recently.
My 2000 PCM had pretty shocking knock values and not just the Burst Knock tables. Im talking attack and decay values as well as sensitivity etc. Default was for all cylinders to act the same. Of course with the sensor sitting right besides some cylinders and further away from others, this doesnt make sense. I basically put the table from the 285KW HSV in there, though I understand the 02 Camaro is also a good baseline for testing. Anyway my weird hesitation from 2000-3500 is now gone, the car is running much better than it has done before. Timing is quite hardcore at around 32deg. I read that the ideal timing is around 26 deg or there abouts. So with this in mind I pasted the spark table from a friends tune in. He had spent months on his and was rewarded with 240rwkw on a stock engine with standard bolt on's. His timing table looked much closer to the ideal. I have also commanded my AFR at all RPM and Load points using the custom OS table in EFIlive. At low loads I have 14.63, heading to 12.9 at 3600-4400 then back to 13.1 to redline.
I did this based on some threads on efi101.com discussing the ideal AFR ratio for performance on LSx engines.

So in theory if my VE table is good things should start coming together soon. Speaking of the VE table. Some interesting observations there. On a long trip with 9dec IAT temperature I was running a little leaner than commanded, however around town it showed as richer, maybe due to IAT sitting at 40deg.. I was considering messing with the new IAT table, which I did in fact do, putting a 5% correction factor in, though I cleared that until I get the VE done at one temperature as it was making me chase a moving target. So the plan is now dial the VE table in fully then configure the IAT correction table in the custom OS to correct mixture. I think it will only be around 3% as my 5% factor was too much.

Cam install is penciled for March 06. I should have all the bits together by then. Im tossing up whether I should get some comp 918 springs as I understand I have 915's in there already, but this is not confirmed. The lower seat pressure of the 915's might be better for the components.

Ill almost certainly order a new Powertorque Over the radiator cold air intake (otrcai) to cement my tune in mafless mode.

I have a trip to Yorkshire next week, so lots more logging and ve table tuning to do. Im pretty sure the frequent parts are tuned already. I guess I should do some smoothing to make it look normal as at present it looks like the rocky mountains with a nice smooth valley in the middle.

Read an interesting article on octane. Basically no point running a higher octane as it actually burns slower and with less energy than the lower octane UNLESS your engine is designed for it. (ie) High compression etc. Basically if you can run timing at the perfect point without knock, then running higher octane may well lose you power and cost you more. So I guess thats well and good that I have been happy to use 95 octane and tune for that rather than mess with 98. Perhaps if I was running 11:1 I might.

A new begining

Hello Mr FedEx man, thats that you have. A nice shiny new camshaft. Excellent. Now Im wondering if I have gone too large on the cam. Probably not, but looking at the lobes, they are awfully square looking, lots of high lift and the lobes pretty much match the bearing journal height.
Maybe I should have got some springs to replace the comp cams 915's Ive got in there at the moment!? Im sure a lot of others will tell me I doth protest too much, its only a 220/224 afterall. We will see, its advertised duration is actually quite large at 282/286 with 57deg overlap! Hopefully the cats can do their job and clean up the tailpipe mess or things will get interesting.

On that topic Ive been reading up on "emissions tuning". This usually consists of altering the mixtures to a leaner state, rasing the engine temperature through controlling the fans, rasing the idle speed and maybe altering spark timing. This can make some difference. Anyway thats a year off so we will worry about that if/when we need to.

Did a couple of short runs to start getting the Autotune feature working. I scaled the whole table up 10% as Id already done plenty of LTFT tuning so thought it cant be too far wrong. Seems to have been maybe 5-10% out. Anyway lots of driving required. Lucky friday Im off up North so should get near on 500Mile round trip logged. Certainly a tune on the way up and room for another on the way back. Im sure timing needs revisting again. Though a small amount of KR was still noted. Seems to have lost a bit down low, but starts going crazy up high. Perhaps thats just perception. I need to do some 0-60 runs again.

Wideband!

Well thats the Wideband O2 installed.
As can be seen here from a cold start things start pretty lean then richen up substantially until warm and things drop into closed loop.
The LC-1 NB02 simulation is very erratic compared to the smooth stock results.
I might need to mess with grounding wires. Though preliminary checks showed little to no difference. I do however need to calibrate the Wideband properly as its LC-1 stock. Ive had to order a USB to Serial converter. Hopefully that should be in the next day or so.

I can now start AutoVE tuning which basically scales the VE table so that commanded fuel equals actual fuel. This then means that you can do without PE mode and use the custom OS to command specific fuel ratios at any RPM and MAP point. So far my part throttle is pretty good, but Ive been running with no PE or enrichment for a while and avoiding full throttle, so hopefully things will start moving pretty well once I get it the VE table sorted out.

Slow and steady progress

I bit the bullet and ordered the 220/224 cam. Basically the Crane grind though at a much better price. Should be on its way for an 06 installation date. I also won an LS6 intake and injectors on ebay for quite a low price, so that should give me more injector and manifold flow for the cam.

After a day spent figuring out how to wire up the wideband and lying on the 13deg C driveway in London hefting on the narrow band stock O2's (NBO2) I finally worked out what went where and being late Autumn of course it got dark so I had to put the stock sensor back in.

The solution it appears, in my mind anyway, is to locate the LC-1 controller in the cabin and drop the Wideband (WBO2) connector down through the shifter hole as the sensor sits basically at the base of the trans. This will give me easy access to the wideband connectors for efilive and calibration, plus keep it out of the weather. Just the Narrow band inputs to the PCM need to go down under the car and the WB02 sensor. So the next stage is to remove the console. Im going to need to do this again when I get the "ripshifter" which I already have sitting in NZ. Hopefully all the LC-1 controller and most of the cables will fit under the console out of site. I really only need a couple of wires available for efilive. This might be a 3 stage process due to time constraints;

1. Disassemble console
2. Wireup LC-1 in NB02 and WB02 mode
3. Reassemble console

Stage 2 is the one which will require dry weather as Ill need to grovel under the car on the driveway again. Though now I have the wiring figured out and a block connector wired inline things should be a lot faster. The old O2 sensor now has a good dolop off anti-seize on it too so should be slightly easier to get out this time.

I should mention that subsequent to my burst knock adjustments the car goes significantly better at part throttle and off idle driving. I have disabled PE mode which runs at over 60% throttle and higher MAP pressures in order to doublecheck my VE table. I expect to turn it back on soon as well as revisiting my timing tables, as I suspect I may have pulled a little too much out in places. Hopefully Ill have the WB02 in well before then and be on the way to a solid baseline.

I also did quite a bit of smooting to the VE table. It looks pretty stock now, though its a little higher in most area's. Still a way to go though.




It looks like running the car on a dyno for spark tuning is the best idea, its virtually impossible on the street to tune for best advance as you need to hold a certain load and RPM point while adjusting spark to verify maximum torque. Apparently maximum torque is also usually a good way from knock point. I found that interesting. I guess Ill have to find out how much dyno time costs once I get the tune dialed in as best I can. Ill also keep my eye out for a dyno day as Id like a proper baseline.

So next step, wideband install. Hopefully sometime over the next week.

Welcome to the real world

Ok, dispite some initial excitement and quick learning I have now realised that to advance is going to take some considerable effort and time. I have done countless updates of the PCM in the last few weeks and almost started again today as I had a weird hesitation from 2000-3500RPM.
I tried a GTS tune which didnt help any and compared the maps I had done, surprisingly (or otherwise) the spark and ve tables were close, so I thought the issue must be elsewhere. Sure enough after some suggested logging I captured the culprit, BKR or Burst Knock Retard. This little blighter, which is especially hard on SD tuned vehicles, retards timing based on a preventative algorythm. It basically checks for delta airflow values which exceed a certain amount and retards the ignition based on a table. Suffice to say the table and airflow values have now changed. The stock Holden GTS has more agressive settings, while I have gone even more aggressive.

I have also learnt to check for knock sensor voltage while also monitoring knock. This allows you to differentiate between "false" knock, and real knock, as the sensor will be jumping around when real knock occurs and be fairly quiet when false knock is about. Of course false knock can be ignored except for the fact that it can mess with your timing. A partial solution is to tweak the "knock retard recovery rate" table to recover quickly. Knock being a potentially ruinous situation always requires care.. as does running too lean. (Hence a wideband is seen as fairly essential for tuning).

I have therefore ordered an O2 sensor socket so that I can pull the old one out and make up a harness. This will allow me to transfer the sensor to a friends car rather than a permanent fixture in mine. Hopefully I can get the blighter out. I spent a few minutes with a cresent the other day hefting on the drivers side O2 to no avail. I think a large lever is called for.

Im starting to consider what to do once things are tuned right. This isnt likely to be any time soon. Perhaps early next year I can consider things to be "ballpark". Id then like to do at least a cam swap, perhaps heads and intake. In fact I just bid on an LS6 intake and injectors in Oz. Would be a good upgrade from my current LS1 and 26lb injectors at the right price.

Im considering an SDPC custom cam, which is in effect an off the shelf Crane jobby. Specs are 220/224 and 0.551 lift. Or 0.583 with 1.8 rockers. Should be good for a 12 sec 1/4 or 11's with any luck. That should do me for a while. Heads and intake can wait till I go for a 402 stroker. (Which isnt planned until the engine wears out or I kill it, whatever comes first!).

So in summary, lots to learn and lots of time required to learn, but as long as I pick something new up each day we are on the right track. New 0-60 times to come soon.

Not easy

A reflash to manual calibration today to set right the trans issue. Seems to be the accepted way of fixing. I never did get to the bottom of where it was set in the calibration.

Also some slight errors in adjusting my VE table, I was using absolute values rather than percentages. Tordne lent me a hand with a calc_pid. I was making 50% changes rather than full value, but still was going down the wrong track. I do definately need the WB LC-1 installed so will make full effort to achieve that in the near future. Will require an extended session under the car with a large lever and a good spanner. I also need to check my O2's. Learning lots, not stuck yet, but the more you learn the more you know there is to learn, its certainly not a quick fix situation.

Gathering momentum

As expected I wasnt paying attention, I had placed the .cal files from the Custom OS's into the wrong place. Once they were in the right place a reflash of the tune worked fine. So Im now running OS3 with dual spark tables in SD mode. The software reads the cal files so that it can understand the PCM OS, I was running off the old ones still.

Efilive with custom additional features, like support for dual spark maps and forced induction.



After 2 passes at updating the VE table I am now hanging around -5 to +2, so Im almost there Im now making changes at 50% the recorded rate. One thing I noted was with the second flash and another 10 on average (max figure of 115 so far) added into the VE table things seem a little sluggish down low. Maybe things are a little rich at this point. Timing has remained unchanged, though I think I need to pull a little more timing out as there is a little knock retard at higher RPM. I guess I might even need some more timing down low the idle timing table is set to an 8 degree advance while redhardsupra's site recommends around 20. Though admitedly this appears aimed at people with cams.

Now is a good time to add some pictures to my boring text only blog, so here is the current state of the VE table.



I started reading up on the next step, which is idle and timing tuning. Idle is pretty good, though I need to make sure transition to and from idle is good as this might have something to do with the sluggishness Im feeling down low now. As usual the most excelent forum LS1tech.com has a thread to cover this topic as does my fellow blogger redhardsupra here. There is also an excellent link to what appears to be a foolproof method of recalibrating MAF's. Which I may do to allow extra data logging for tuning, though I expect to lose the MAF longer term.

My baseline tune was from an Auto and I suspect I may not have "cleaned" it out as much as I need to. The car drives fine, but Im still trying to figure out how to get the scanner and tuner to read it as a manual. Either Ill have to flash with a manual tune or will figure it out soon enough. Good old EFILIVE forums are very good for data gathering.

Starting to get into it

Yesterday was a very enlightening day as I had almost the whole day to replace the oil and do some tuning.

The old R8 neeeded its skidplate removed to give me access to the drain plug and oil filter. Thankfully the filter looked reasonably new and wasnt on too tight, a slight mess on the driveway later and 4L of 15/40 and 500m of 0/40 Mobile1 later and we are good to go.

I decided to update to efilive custom os v3 which was relatively straight forward, after flashing the base OS in and then flashing my 260KW HSV tune back in all "looked" well. I made the recommended alterations to the custom parameters and fired it up. The idle was shocking and it seemed no better at higher RPM, the car stalled.. Ok so checked out what was happening and reset idle to 800 rpm, still no good. Maybe I wasnt paying attention and did something wrong.

At this point I decided Id go back to the OEM OS, but decided on the 285KW tune instead. I will get a tune happening on the stocker then have another go at the custom OS. The 285KW tune was for an Auto so I had to disable some codes and copy and paste a few of the trans fields over from the R8 including speedo settings. The car fired up no problems, there is a lot more timing in this tune over the 260KW one, in fact thats where most of the changes seem to have taken place. After going for a drive I found out as others have suggested that the 285KW tune is a little "sharp" on the timing with up to 4deg Knock Retard recorded. So a little tweaking to pull timing from the high octane table as indicated by the logs and another flash, though as well as pulling the timing I decided it was time to go Speed Density (SD) mode and start tuning the VE table properly. The MAF was duly unplugged and the P010x MAF MIL (SES warnings) disabled.

Now are are cooking on gas! That made a big difference, the car now no longer feels like a slug sandwich down low and jumps off the mark, a review of the logs shows no knock either. So a good few minutes of warmup to let the Long Term Fuel Trims (LTFT's) get themselves together and I logged using "Black Box" mode some data. "Black Box" mode allows EFILIVE users to log data in the car without a laptop, just a small cable connected box which can be tucked out of site. The box has about half a Mb of space, enough for me to log 40min with 9 PID's. The default is a load of tiny files which were not much use, so I have reconfigured for one large file. I really must read the manuals!

Ive updated the VE table based on the RPM vs MAP vs LTFT bank 1 results. Going forward Ill update the Map to average bank 1 and bank 2. As a side note injector duty cycle was at 25% at 2500 RPM, Ill have to check it at motorway speeds under full throttle, though for LTFT tuning hitting PE mode is a no no, as the PCM dumps in extra fuel so you wont get any useful information for tuning.

So a new VE table with values about 10% higher then smoothed once retaining high and low values is the result. Lots more logging and tuning over the next week or two. Off to Wales this weekend to see the All Blacks destroy the Welsh so should get plenty of logging and tuning done.

Base OS upgrade

Lots of reading and scanning this week. I noticed that Engine Coolant Temperature wasnt being measured in the default PID's, it would stay at -40C. Weird, no codes where thrown so I guessed it must have been ok. In addition it was shown ok using the bidirectional controls for idle. I noticed it was set at priority 3, so bumped it up to 1 and low and behold it came to life and now works ok in the scanner. Cool.

My LTFT's were all +10 in the higher ranges, so certainly room for improvement there. Im tempted by an EFILIVE custom OS as it allows dual spark maps and octane/spark scaling dynamically in SpeedDensity (MAFLESS) mode. Only issue is that the OS doesn't support any calibrations from PCM's before 2001. So I downloaded from this excellent Holden Pcm site a stock 2003 Manual R8 Clubsport PCM OS image and Calibrations. After firing up the stock 2000 tune and the 2003 one to compare I noticed not much had changed. There was some alterations higher in the RPM range to the Volumetric Efficiency (VE) table, but nothing stellar, certainly not compared to the GTS tune. There are numbers well over 100 in there. All looked well with the main action required to copy the fuel injector flow rate table over. The 2003 model injectors appear to flow around 10% more. I think from memory 2000 are 26lb/hr and the later years 28lb/hr or there abouts. I guess Ill need to keep an eye on duty cycles, which coincidentally were also not reading accurately. I might have to fiddle about with the scanner to get them reading ok. Again no DTC codes are thrown and the car drives ok so I guess its down to the scanner PID settings.

It was then with a little trepidation that I fired up the tuner and ran a test flash. Some nice warnings about isolating the Class-2 network from the PCM, which I duly accepted and the test worked fine. I ran it again and it went in fine, a power cycle of at least 15sec and then everything fired up 100% no codes or anything, a drive around the block and all is well. I couldnt say I noticed any more power unlike the cleaner air filter, but it seemed a little "fuller" at lower revs, less peaky. I can now mess around the the PCM and know that my tuning can be transferred to the later PCM. Its kind of tempting now to throw a 285KW HSV tune in, which should definately give a little more power, but that will just delay the proper tuning process. Next step Speed Density mode and VE table tuning. Winter is approaching so I need to get my Wideband in while I still can. Being in London the only place to do this is on the driveway!

The end of the begining

Is this really the end of the beginning? I hope it is, rather than the beginning of the end.
Ok enough metaphysical claptrap.

First drive since the clean up today. Noticed a decent spot of rust bubbling around what appears to be a crossmember bolt midway down the enginebay, its not come through the paint yet, but she is a cruncher. So I think Ill hack it open and douse it in anti rust/corrosion treatment. Hopefully its not gone right through and its just a surface issue.

With that in mind I booked the 'Orange Pig' (Tiger Gold R8) into Before-n-After in Newbury about 1hr west of here. He is fully booked till late December though. Basically coats the inside and outside of the whole car in a protective coating of Waxoyl and gives a 5 year anti corrosion guarantee. Not bad.

So back to the main theme which is performance modifications and analysis.
I managed some good times today, 5.82, 6.08 and 6.20, quite an improvement on last time.
I have to put most of this down to cleaning the air filter which previously was pretty much like having the engine breathe through a cow-pat.

Also the cold air intake has a large diameter pipe from the airbox going to the shielding which sits over the radiator this was disconnected and basically performing no function. I hooked this back up as well so I guess this will now let quite a bit more cold air into the engine.

EFILIVE was nice enough to replace the parcel which NZ Post now says they have no trace of being posted. A replacement was sent via DHL yesterday and I got a call today to say it was here and the nice VAT man wants £100 off me! Aside from that little pain I am now able to commence tuning from this weekend. Ive done all the free mods I can, its onto the costly stuff now. By all accounts I should expect up to 50KW/65BHP from a tune. Though Im sure it will have to be pretty good to get me that much. Ill be taking it in steps.

Stage one tuning will be to do a lot of scanning and see what is going on, see if I have any knock and take a look at whats going on with the sensors etc. So far the Check engine light hasnt resurfaced so maybe a few long runs has sorted that out. Next will be the VE table and to get rid of all trace of 'Abuse Mode' or 'Torque Management' as it is euphamistically known.

First mods

After the lackluster 0-60 times I wasnt surprised to find the air filter corrugations literally filled with dirt. I doubted the K&N had even been looked at in its life. Stock it should be good for 6.2 sec 0-60's. The screws holding the filterbox lid down were rusted through and i had to drill one out to get it off!

Much washing with the hose and rinsing later and it was in much better shape. A more thorough clean is in order when I get some K&N filter oil to recondition it after cleaning.

Oh dear so much for full service history! The main dealer who sold it obviously wasnt interested in anything like preventative maintenance. I suspect the oil was never checked since the last service which was around 5,000 miles ago. The oil level still seems fine after 500 miles. Ill monitor for a little longer, though a full oil change is now planned, and due, especially based on the shocking state of the air filter.

I Contacted EFILIVE to chase the tuning software, I have the LC-1 now, though getting the O2 sensors out of the exhaust may prove impossible as they look well rusted in there. Could be an interesting sequence of events..

The throttle body bypass was quite simple, I plugged the output tube into the input tube bypassing the throttle, didnt need any kit or anything. Also set the airbox up properly as it was all loose and wont have allowed much cold air in. The engine cover is also now removed to help prevent trapping in heat .

So another run of Mr GTech and we will see if the clean up has made any difference. If there is any change its likely to been mainly related to the air cleaner, it was totally clogged!

Baseline

Well on collecting the LC-1 today, I managed to do a few 0-60 runs with the g-tech.

2 x 6.52sec runs and a single 6.70sec run. The plan will be to do 3 runs and drop the worst one. So lets call the first baseline run an average of 6.52 sec.

Next mod will be to bypass the TB and remove the engine cover. I saw a dyno showing basically 6 bhp and 7 ft/lb gain from the TB mod. We will see.

A fellow pistonhead has an old O2 sensor for me so Ill post him a fiver to send it back to me.
Im not sure what a stock R8 is meant to do, but the Wanali or whatever tyres at full road pressure probably dont help, nor will the traction control, which I forgot to turn off. Never mind, as long as I do all the rest the same it should at least give a "relative" idea of performance.

Chasing EFILIVE for their scanner as its just gone 10 days. Hopefully its not far away.