1992 TPI system on top of a Goodwrench LM1 290hp crate motor with a 5 speed. When my motor is cold and also during warm up if I floor it I can only get the revs to about 3500 to 4000. It starts to pop, sputter, buck etc. I can't really tell if all the noise is coming from the intake or exhaust, my mufflers are pretty loud. It runs fine if I let it warm up for a good 15 to 20 minutes of driving and it runs absolutely perfect! I run mid 12 sec 1/4 miles with it. Any ideas? I am running a Street and Performance chip. K&N at the throttle. Stock rams style exhaust manifolds. Everything is new, sensors, plugs, injectors, fuel pump etc, etc. Oh by the way, all this is stuffed into a 1987 Fiero GT.

 

check fuel persure at 3500 rpm and timing

 

sounds like its running rich while cold....