Its a 92 gsx with 174,xxx on the chassis and 6,xxx on the rebuilt engine

 

ok well update. i got to the muffler shop, and the guy put it up on the lift. he looked under, and the guy who owned it before had a temp. pipe for the exhaust. so the dude welded a new pipe on, then there was a clank noise, the pipe hit the drive shaft. well he bent it down. the dude who had the car before me, had a 2 1/4 pipe to the cat, then 3' pipe from cat to muffler, and the muffler was 2 1/4, like atleast use the same size pipe. well the backfiring stopped, but the engine still stutters. and im losing oil. quick. the filter needs to be replaced and the seal too. so ill update more after that, also i kinda cracked the timing belt cover also.