basically my fc has no power wat so ever from 3800 and up if i floor it in any gear. if i press my gas about 1/8th of the way down i can accelerate past 3800 but if i floor it i can't. By the way its not my 5th and 6th ports cause i checked them out they are not jammed and i just purchased a brand new cat and am getting more then 5 psi outta the backpressure tube. i believe it may be my secondaries but am not sure. Its a 1988 gxl with a 1986 13b na engine. Any help will be greatly appreciated thanks Peace

 

My money is on your secondary injectors not firing.

 

i'd say its the secondaries aswell....

 

Yeah there was a guy who had the same problem. Could not get past 3.8k rpms WOT but with partial throttle he could. Turned out that the 2ndary injector wiring was messed up.