my tuner figured out why my car was running lean.

[ADRENLN]

i also have a blurry pic of the gians through the rpm range. only the last part matters anyway. you notice im gaining, then all of a sudden at 4000 rpm, right where i start to richen up again, i gain almost nothing. then it starts gaining good again in the higher richer rpm's.


dont know if this helps anything. any ideas?

[/IMG]

 

[hognutz]

most guys with my mods are 290-310 rwhp, hmmmmm. well, im at 286rwhp with somthing wrong with my tune. i dont know if numbers will increase if we fix it. however even if i stay at 286, i have blower cams. so if i had na cams like most of the #'s you see that are 300rwhp, id prolly be right around 300. its is a dynojet,so its about right.

hey trust me, ill take more power if theres more to be had.

anyway i was thinking the same thing about it staying lean or getting leaner as rpm increased? i dont get why its only in the low rpm

anyone have any ideas?

okay well you sig says 275 I thought that was current. yeah once this tunning gremlin gets taken care of you will likely get some more hp.

can't see how it would be the cam. you have to tune a for the cam period. blower cams usually favor the exhaust a bit on the specs becasue the intake is boosted. my small brain can't seem to figure out why that would lean you out or even if it did why you could not compensate for it.

I am no expert though.

 

[ADRENLN]

wow reeber, i wonder if your right. i wonder if the blower cams have somthing do do with it?

if so i hope that can be fixed with the tune, cause i have no doe for a blower anytime soon, and id hate to pull the headers off and go back to stock garbage.

 

[trinity_gt]

It's noteworthy that the torque curve flattens right around where it should instead be peaking. This is where the VE is the highest. The total mass of air flowing into the engine might be higher at higher RPM but the amount of air filling each cylinder per cycle should be higher at this torque peak than at a higher RPM; higher RPM doesn't necessarily demand more fuel per combustion cycle. That might explain why it richens up again away from the torque peak.

I'd still be thinking fuel delivery or air mass measurement. That Steeda "CAI" shouldn't be causing any problems (if it had a bend before the MAF perhaps...) Have you cleaned the MAF elements recently? Given them a spritz with brake part cleaner to clean off any accumulated filter oil that might cause it to under-report airflow?

My 02 GT made 313-ft-lbs and 268HP on the factory injectors so I doubt it's a size problem. How did the tuner guy determine that the injectors were maxed duty cycle wise again?

 

[Don 95Vert]

It's not transitioning properly, it's taking to long to transition to OL - or the aircharge WOT multiplier is set too low. Or some other problem with the file or a mechanical problem that hasn't yet been discovered.

I've have tuned many, many cars and a several this year have run out of injector. When they do, they go lean at the end of the pull, not in the middle. If the MAF pegs, they go lean at the end of the pull, not at the beginning. As RPMs go up, the cylinders fill faster.

If this is an SCT dealer and he wants help, tell him to give me a shout, I'll be glad to help - not to criticize him, but to lend a hand. We also do on-site training for other SCT dealers and help dealers all the time work through things like this. If he is not SCT... than he should switch LOL!!!

Just trying to help here - if anyone thinks I'm just guessing than that's OK with me too.

Don

 

[ADRENLN]

don, i wish you were a diablo tuner, id tell him to call you. what is ol? i hope yea its not the maf or the injectors. it is somthing he is missing in the tune or somthing. i hope he finds it.

i cant even drive it somwhere else if i wanted to, its too lean.

 

[Don 95Vert]

what is ol?

Open Loop

 

[TweekedGT]

Generally most N/A cars experience dip in in the lower rpm ranges. I know mine does. I can't really tell what your A/F curve looks like from your graph. Most blower cars do not display the erratic A/F at low rpm like N/A cars do. I just can't see your stock injectors giving up the ghost yet. Mine still aren't pegged and I'm running 287rwhp now.

 

[ADRENLN]

tunes all fixedup guys. thanks! details are in another thread.