That popping sound is not back-pressure ... it is most likely one of two things.
1) You are running to rich and fuel is dropping onto your headers and igniting (this would generally be fairly loud).
2) I believe this one is probably more likely.. you have a de-acceleration tune.. meaning when you let off the gas your car runs lean and pops...
either way.. I would definetely check the timing.. too advanced can put that sucker on detonation road!
1) You are running to rich and fuel is dropping onto your headers and igniting (this would generally be fairly loud).
2) I believe this one is probably more likely.. you have a de-acceleration tune.. meaning when you let off the gas your car runs lean and pops...
either way.. I would definetely check the timing.. too advanced can put that sucker on detonation road!
If you are experiencing sluggishness during rev etc, I bet your timing is off. if you just dropped in the distributor from a pic this is definetly your problem. not enough timing and the motor wont rev. or possibly your have miss adjusted your valves if you have adjustables. or even worse on tooth of on the timing chain. not sure what all work you did on the motor but I bet its one of those things. also check the little things like are all the injectors plugged in and firing? sounds like either your timing is off or your a cylinder or more down. I had the same problem once and my fuel injector wasn't firing on the number 5 cylinder. same problem your experiencing, slow rev. good luck.