Diameter of Exhaust?

[SupermanX24]

What's the diameter of the over the axle pipe on a stock LT1 car? I just might do a custom job myself.

[Featherburner]

I think it's 2.75"

[JL8Jeff]

Factory pipe is 2-3/4 and most aftermarket cat-back are 3".

[SupermanX24]

2 1/2. I took the muffler off and measured. Thanks anyway guys

[Tru2Chevy]

Wow....you sure that's a factory pipe? I always heard and saw that all 4th gen v8 cars had a 2.75" factory pipe.

- Justin

[SupermanX24]

pretty sure, the entire exhaust looks stock. I got the muffler off and measured the pipe and sure enough, 2 1/2

[NJ Torque]

Your car single or dual cats, Pat?

[SupermanX24]

single

[JL8Jeff]

The tailpipe outlets are 2-1/2 but the inlet should be 2-3/4 or 3". It actually necks down at the y-pipe connection too.