when i took off my cats, i noticed that the car would backfire when i rev it real high, or if im cruising and i let off the gas... i can hear it backfire in the exhaust while im rolling with my foot off the gas... is that ok? or is there a problem? thanks guys

 

in the exhaust a backfire would be unburnt fuel being lit off by the cat or some other heat source. i'd make sure i had a good tune up, but it isn't an uncommon occurance to have exhaust pop like that

 

I think your talking about backpressue. Does is not it when you first crank it up in the morning and then starts doing it after your car has warmed up? If so thats backpressure.

 

thats just what some motors sound like when they arnt muffled...... downshift and you're hear it alot mroe.

 

even with a full exhaust with my chambered mufflers when i rev it up real fast i hear that pop pop pop of the back fire i love it it sounds sooooo cool its just because your car is dumping gobs of fuel into the cylinders and some of it is entering the exhaust still unburnt so it explodes inside the exhaust.....as long as it is this normal sort of back fire youre not hurting anything.

 

your so right, my car had a burnt wires and i downshifted ne day and i was like WTF this thing gets loud.

 

I knew a person who had a firebird formula, 305, and he wanted it to be louder without investing in a better exhaust system so he drilled holes in the cat (ha?) and everytime he left the parking lot it would tick and sound like the thing just needed to be shot n put out of its misery.