just when i thought i had the timing pretty close, and it was actually running ok with some good acceleration, IT GOES BACK! I was driving it today and i had to stop a little more sudden than usuall, then it started to idle like crap, and started to bckfire out of the carb a whole lot! Now when i accelerate, all i hear is POP POP POP POP!!! Someone please help me. What do i do?