LS2 with GMPP E67 - advice needed
New to this so any advice would be appreciated and apologise if any of these are dumb questions.
Background - we have built a FD RX7 with a Holden Commodore Gen IV L98 (ie ls2 bottom end, L92 Heads) and are using the GMPP LS3 376/480 controller. This controller suits the LS3 with the GM Hot cam so we used this cam as we thought we might end up with a close starting tune. Didnt quite work out like that.
I have managed to retrieve the cal out of the PCM and make a small change and write back and then also write back original tune and again retrieve so reasonably confident thats ok as there was some conflicting reports originally about tuning these PCM's. OS is 19211212
When we first tested the car it ran very rich and I was still waiting to for EFI Live. It ran AFRs of 14 on cruise etc assume that was closed loop sorting things out but at WOT it was like high 9's (so much for the crate engine tune being close) So our only tool was fuel pressure origianlly at 58psi and we just kept dropping it its now round 36psi which I know is real low but thats what we had to do to get a AFR of low to mid 11's. (see attached) Still not ideal but car was a rocket anyway so can only get better with those sort of numbers.
So I have tried to read all the applicable tutorials and threads that might assist and my plan is as follows and would apprciate any thoughts.
It appears from looking at the VVE that the fuel just keeps getting added in flat out at the top end and that they just made the tune rich to be safe. So i was thinking of turning off the closed loop and removing all the LTFT and STFT (per Swingtans tutorial) and then simply take so fuel out of the 2nd half of the map kin small % may 3-4% and see what happens. I dont know if I am quite up for any AutoVE tuning yet.
Next problem to assist with that, some logging would be great but in Scan tool program it seems the supported E67 PIDS are limited. (see attcahed) I made sure I was on lastest version and entered VIN no and PCM type etc. This is what I can bring up but what I would really like to log is - Map kpa , engine RPM, Wideband actual from an LM1. By doing this before we make any changes we can then see in particular what parts of the table we are in so we know how far back down the map on the kpa scale we need to go. Is there anyway to get the PIDs I need to work?
My plan was to just leave it in open loop afterwards. Basically as this is a dedicated raod race car its all pretty much 3500 to 6000 rpm running and so I was wanting to try and keep it simple but I get the feeling someone will tell me its not that simple.
Any advice really appreciated.
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