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 MAP
The 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.
