Why is my car loading up on the bottom end? If I am following cars in traffic and just holding staedy at low RPMs say either in 2nd or 3rd gear and I get a little bit of a clearing to speed up as soon as I go to accelerate the car acts like it loaded up and then you will get a backfire or 2 that is coming from up in the headers somewhere and it will take off. Now I have noticed that while cruising down the HYWY every once in a while at a lower speed(55-60 MPH) in 5th gear it will start to give a slight buck back and forth and a pop from the exhaust sounds like its up in the headers when it pops. But like I said its mostly while driving super slow and being behind traffic. If I just tromp the pedal it runs great. New plugs, wires, TFI is good, cap and rotor look fine, new O2's, I eliminated my coil with another one and it still did this. I pulled more timing also with no changes. I am running 14 initial and 40 PSI fuel. I tried pulling some more fuel out of it last night and it still did the same thing no matter how much fuel I pulled. I tried swapping out my mass air with a Pro M and that didn't change nothing either. I have checked for vacum leaks cant seem to find any. I also changed my TPS that did nothing either. I have checked for codes and other than the typical EGR codes that I have always got with this car because all that stuff has been removed their are no other codes. This is a brand new motor I just put in 2 weeks ago. I didn't have this issue with my old motor. The changes that were made were 306, GT-40Y heads, and Trick Flow street heat upper and lower. Everything else stayed the same. My old motor was a 302 with GT40P's and a Edelbrock performer upper and lower. Check my sig for what my new combo is.
