1990 highly modified 434 corvette tune issue

[bjankuski]

I am trying to tune a 1990 corvette with a 434 CID with 60 lb injectors and I am having a problem, and am looking for some advice. The car idles and drives fine at light throttle but as soon as I get past 25% throttle at 4 volts on the MAP sensor the car appears to go into some sort of limp mode. The car will stumble set the check engine light for a code 33 and cut the injectors pulse from 4 ms to 2 ms. So far I see nothing in the tune that will cause this, any ideas on what is happening? One other issue is if I go straight to full throttle it does take off but my pulse width gets limited to 6.9 ms and the engine goes lean at high RPM.

[RobertISaar]

it was discovered long ago on thridgen.org that 8D had a fueling quirk like this that only happens on large displacement engines(or maybe it was large displacement and large injector? either way).

http://www.thirdgen.org/forums/diy-prom/276420-8d-pw-limit-fix.html