Fuel Mapping Issues

[thermal izod]

Hey all,

OK, I had some electrical issues this week at the track (turns out it was a bare AC sensor wire), and went to autozone to get an OBDI scan....It revealed that I have a lack of fuel flow under high acceleration, and a right bank O2 sensor not heating up quickly...I have a Mild cam, cat-back exhaust, and a custom 3" TB to Filter fender well intake. Apparently my PCM isn't able to feed the engine enough fuel at the tail end of the 1/4 mile (check eng light comes on everytime). I'm guessing that it's time to get a chip instead of headers next. I have a 93 z28, w/ the above stated mods. Can anyone point me in the right direction for a chip for this car? Seems 93 is a tough year to shop for...

Thanks,
Tim

[wrightz28]

If it's leaning out, probably from the cam, you could get an adjustable fuel pressure regulator, start at stock and then bump up a few psi 'til it cures

[thermal izod]

ah-ha....so u think there may not be a need to chip, or re-tune? An adjustable fuel press regulator might do the trick?

-Thanks

[wrightz28]

No and yes.

No to not upgrading the PCM, definatley wouldn't hurt anything. It would also help it detemine spark curve a little better.

And Yes, a AFPR at a slightly, dont' go ape, but slightly higher than stock would be of help. The cam, although mild is allowing the motor to inhale air better, so it's leaning out when the intake vavles are open bigger and longer now.