99 Corvette - unable to adjust injector slope

[bkel33]

My car is a 99 LS1 C5 corvette with heads, cam, rockers, injectors, nitrous, headers, A4 auto transmission. My wideband gauge reads about 9.5 on part throttle. I have changed the injector slope to adjust for my larger injectors a pretty significant amount, but my a/f ratio doesnt seem to change any. The car is running pretty rich. Anyone have any ideas/ suggestions?

BTW - my LTFT are about -15, i've added about 30 to the injector slope but no change

[mikel]

Wow.

Not sure where to start here....

Has there been any custom tuning done to this car? Was it tuned for the heads and cams?

Ideally, if it has not been already, you NEED to get this thing tuned up on a dyno with a good tuner.

The heads and cam are out of the realm of adjustment we provide in the Predator, and will require extensive changes to the tune that can only be done with our CMR software.

Get in touch with one of our tuners and let them dial it in for you.

[bkel33]

So I have to pay someone to tune my car before I can tune it? I'm pretty sure this is why I bought the predator to begin with...

[johan]

Your a/f's being 9.5 at part throttle is an indication of something is haywire, if you have stock injectors there is no way the fueling is that off, the pcm will always try to correct back to 14.7 :1 and if you see 9.5 at part throttle you have another issue here, maybe front 02 bad, does it throw any check engine lights, if so what codes do you see?

[bkel33]

The car runs, but is pretty rich. Should I crank it up as far as the predator will let me? I just find it odd that changing it by that much made absolutely NO change to the A/F ratio.

[bkel33]

The stock injectors have been upgraded, as noted in the original post
The only code it throws once in a while is P0300 (because of going with such an aggressive cam)

[concoursd]

are you using the stock MAF sensor? with a 9.5:1 A/F ratio at part throttle you must be getting a CEL. or there is something wrong with the wideband or the oxygen senors on the vehicle.

[mikel]

No, the A/F is a result of larger injectors not being scaled properly.

OP, you MUST get this car tuned by a pro, no amount of fiddling with the Predator is going to even get it close.

A good CMR tune will have it running like stock.

[bkel33]

The MAF is factory. I suppose I will get a good base tune and adjust from there. Anybody know of any reputable dyno tuners here in Colorado?

[concoursd]

Mikel I didnt think the MAF change caused the problems solely. I thought he had already adjusted his injector slope properly.

[bkel33]

Would I be able to get someone to send me a CMR for a ballpark and then adjust from there? I am a little disappointed with the limitations of the predator...it seems like it can't do anything that I bought it for except delete the rear o2s