i was just wondering what causes backfiring like when your going down the street and you here someones car make like a gun shot sound.or some peoples pops all the time.is it just the carb and timing or what?

It can be either one of two things. Either the incoming fuel mixture ignites in the intake manifold (backfiring) or fuel ignites in the exhaust system (afterfiring). Misadjusted ignition is usually the culprit to backfiring, and an overly rich running engine usually causes afterfiring.

so back firing is that black soot youll see on the inside of your air cleaner lid and the loud bang from the exhaust is really afterfiring?

I just put my carberator on and this is the first time since I had my car it started backfiring in 2 different scenarios

First time was driving around in second or third gear at a low rpm. I floored it and it backfired. TIming?? I also dont have my kickdown linkage hooked up.

Second time was when it was in park I was reving it up and probally around 3500 rpms or so it backfired.

I havent touched the tiiming since I put the new carb on. Would having the timing too retarded cause this?