Every once in awhile my car back fires going into second gear. It only happens when i shift from low RPMs right around 3 or 4. If i get on it and shift at 6 then it doesnt back fire. What could be causing this, could it be the fact that its straight piped???

 

Yes, also might be running a little rich

 

is it a back fire or after fire. backfire comes through the intake mani which doesnt sound like what you have. it just sounds like you get afterfire pops from being rich or as you asked...a test pipe. its normal if you dont have a cat.

 

mine is doing this as well... first thing is check your timing and valve adjustment... i did this and everything is cool... then i thought i had some bad gas so i put in a full tank of premium... nope... im thinking i may have a slightly burned valve or something of that nature

 

It must be the after fire that your talking about. I just bought the car from a friend of mine so im working out the bugs. Its prob nothing i should worry about then huh?