LS2 with GMPP E67 - advice needed

[V8RX7]

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.

[alian]

Sounds like an interesting project.Never think any question is dumb. Someone else has probably thought the same thing.Wow that ve table looks interesting. Can you get a look at somone elses table that has the same engine so u can compare.I am sure that arond 58 is right for the presure. Its the ve table that needs some work.Not sure, havnt played with e67 but cant imagine that the ve table would look that different unless boosted and there has to be a host of pids there to use. There is some very smart people on this site of which unfortunatly I am not 1 of them. but welcome anyway.
Cheers Ian

[ringram]

Yeah just follow the tutorial mate, you need to open loop and disable maf first, then sort out your vve tables with the wideband error % then you can hook the maf back up and do that same etc.
You should get fueling all nice in the end.

My problem was the opposite, lean under wot, I just quickly added 10% to the high map vve until I get the wideband logging setup. But Im in speed density and running off the vve anyway.

Actually your maf should be telling you whats up. How have you mounted it? Whats your commanded PE table say? If you are running the maf it more likley you maf table and commanded pe that need looking at. Anyway you still need to sort out vve first as per the tutorial... so do that first otherwise you will chase your tail all the time..

[55chevdelray]

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.

Noticed your thread. I'm doing the same combination. I have the LS376/480 crate motor and the GMPP matching controller. PLease post any info that you have about how you're doing! :thumb_yello:

[gmh308]

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.

How you doing with this V8RX7?