[Abrown2006]

Ive been searching on the net and the forum but seems like mobile internet doesnt pull up the search info as well as my pc did when I had searched this in the past. Ive found a few threads here and on other sites but each thread has different sizes. Some say 2.75 or 3" before the cat. I know its bigger on the y-pipe side.

Cutting my cat soon and getting ready to purchase some pipe to get it lined out to match with my new exhaust before I cut it off so I can do it all at once

 

[Viper]

Downpipes from the manifolds are 2 1/4" 2.25 and the Collector is 2 3/4" 2.75

The stock exhaust is 2.75" after the convertors.