I didnt read this post, so if you alreayd fixed it then lemme know.
I had this identical problem, and we have the same heads.
It took me forever to rid myself of it. I finally reset my TPS to .99, set the IDLE about 1000-1100 rpm, made sure the maf and everything was hookd up right, and not gettin air turbulance. Moved my timing up a couple degrees, and got an adjustable FPR and played w/ the FP.
Then I disconnected the computer for 35. Let it completely reset. THen hookd it back up. Ran the car for 5min idling, with no accessories running. After that took it out for a normal drive, and then slowly started driving it harder.
The car has improved ever since.
Try it.
Skyler
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-1989 Saleen Mustang #406-
TFS TW Heads, E-303, Edelbrock intake, 70mm TB, 73mm MAF, 24lb injectors, 1 5/8 shorties, Off Road H, 3 Chamber flows, Jaz Race seats, Back seat removed, sub-frames, Roll Cage, and a 80 shot of N20.
12.54@107.4 Motor
332RWHP, 350rwtq