stigmundfreud
July 4th, 2010, 09:14 AM
Guys,
long story short, friend of mine recently had his car tuned but it has returned running worse than when it went in. Car has been stroked to 6.8ltr, not sure on the actual configuration but is also running a 2bar map and a Harrop122 charger.
Attached is both the tune and a log file from today. Unfortunately the LC-1 died just before the run started so no wideband logging. Looking at the stft and ltft I'd say that things are not as good as they should be, by some distance.
The car is mafless but the tune hadn't taken this into account. I've modified the tune to set the MAF frequency fails to zero. Re-enabled ltft just to aide in logging whilst the widebands are out.
PE enable has been set to 15 from 80kPa.
Other than the trims I noticed when my friend was entering into PE mode, timing was being drasitcally pulled. I'm running on the assumption that as the MAF has been removed/failed that the car is running from the low spark table, worth moving the high spark table into the low spark table as per Auto VE?
My other concern is IFRs. The tuner has, in the past, been known to just adjust on flow rates to get AFR dialed in for PE mode. Having never worked on adjusted injectors or fuel systems, is there any guide on how to calculate what injector settings should be? Pulse Width, Flow Rates etc based on the new size and the pressure of the fuel pump?
Ultimately until my friend manages to get a decent wideband hooked up, is there anything that can be attempted just to bring things in line a bit more than having trims up to 30% out? I know it would be dirty but anything has to be an improvement.
Please find tune and log attached.
Cheers
Mike
long story short, friend of mine recently had his car tuned but it has returned running worse than when it went in. Car has been stroked to 6.8ltr, not sure on the actual configuration but is also running a 2bar map and a Harrop122 charger.
Attached is both the tune and a log file from today. Unfortunately the LC-1 died just before the run started so no wideband logging. Looking at the stft and ltft I'd say that things are not as good as they should be, by some distance.
The car is mafless but the tune hadn't taken this into account. I've modified the tune to set the MAF frequency fails to zero. Re-enabled ltft just to aide in logging whilst the widebands are out.
PE enable has been set to 15 from 80kPa.
Other than the trims I noticed when my friend was entering into PE mode, timing was being drasitcally pulled. I'm running on the assumption that as the MAF has been removed/failed that the car is running from the low spark table, worth moving the high spark table into the low spark table as per Auto VE?
My other concern is IFRs. The tuner has, in the past, been known to just adjust on flow rates to get AFR dialed in for PE mode. Having never worked on adjusted injectors or fuel systems, is there any guide on how to calculate what injector settings should be? Pulse Width, Flow Rates etc based on the new size and the pressure of the fuel pump?
Ultimately until my friend manages to get a decent wideband hooked up, is there anything that can be attempted just to bring things in line a bit more than having trims up to 30% out? I know it would be dirty but anything has to be an improvement.
Please find tune and log attached.
Cheers
Mike