so today i just found out i have 3 inch exhaust. I new my car had more of a growl then others since a kid in my school also has a firebird. But my ? is how do i no what kind it is. WOuld there be any markings of the company or anything?

 

look at the muffler and see if theres any rand markings. it could just be a custom job...are they mandrel bent pipes or no?

 

Three-inch at the y-pipe or three-in at the cat-back? If it's the latter (really a 2.75), it's probably just stock. Here's a link that might prove helpful:

https://www.thirdgen.org/forums/show...hreadid=215739

JamesC

 

i look tomorrow for markings but i dont think its stock. I messured it the good old fashion way. String and then measure the string. it came out to be 10 inch long and when rounded seemed to be 3inch. now i dont know what u mean by mendrel bent so what do i know lol.

 

Mandrel bends are smooth and unwrinkled to allow better flow. If your system is stock, you'll see those wrinkles where the pipe is bent. Sorry, the link didn't allow the pic to be seen.

JamesC

 

well if your car has exhaust tips, see if there markings on them.. flowmaster kits usually have flowmaster written on them.

also measure the case of the muffler and compare those dimensions to catbacks out there.

 

Most aftermarkets have no heat sheild covering up the muffuler. If you do it will be stock more then likely. Adam :-)