Engine Misfire After H/c/i Swap

[Landon116]

Makes sense, just don't get sucked into the trap of replacing every part. Assume that any part that was fine prior to the swap is fine now.

For sure that points to a misfire on the driver side, now of course if it's distributor/coil related it could be happening to both sides. Are you running stock headers? I've heard that stock headers have good chance of arcing cylinder 7 (drivers side) with gt40p's.

Well after injectors plug wires and playing with timing I still have a bad misfire. Hardly any power. I have noticed that it occurs much worse when the car gets warm. And will not do it while idling. Can messed up valve train do that? I mean I thought if it was a bad mechanical problem it would do it sitting still when revved. I can accelerate slowly up to 5,000 rPms if I want to its just when I go past 1/4 or half throttle. I can rev it in nuetral as high as i want to and its fine. I know it's hard to help over the Internet. I'm just at a loss after putting everything I have into the car.

 

[Dave2000GT]

Could be mechanical, but i agree youd probably have other noises and symptoms. Did you gap the 764s? Too wide gap can cause miss, my gt40ps dont like them gapped over .050" and get some missing there. stock autolite 764 gap around .044" seems to be perfect. Double checked the firing order? Cap, rotor? Distributor and timing?

 

[Landon116]

Could be mechanical, but i agree youd probably have other noises and symptoms. Did you gap the 764s? Too wide gap can cause miss, my gt40ps dont like them gapped over .050" and get some missing there. stock autolite 764 gap around .044" seems to be perfect. Double checked the firing order? Cap, rotor? Distributor and timing?

I gapped them somwhere near there. I'll check them again. I have a new coil I'm gonna test on it too. But how do you like your p's? What spring kit did you use ?

 

[Landon116]

Update : fixed the problem. Solution was to turn the whole MAF housing about 90 degrees. I belive the Maf sensor was picking up turbulence in the intake tube. I also reduced the gap on the plugs. Seems to run great so far. Thanks again