looking to get a Catco 9118 cat and a 3" flowmaster cat back. will that work with stock headers and y pipe? eventually I definitly want to get the hooker 2055 headers but cant get them yet

 

You will have to modify the y-pipe at the cat in order to mate it to the cat inlet. But, if you do it right, you'll be ready for the 2055's when the time comes.

(They're typically called stock "manifolds", not headers, although there isn't any technical reason for that.)

 

what kind of modifying are we talking about? I would like to install it myself however if I need to I would take it to a shop and get everything welded instead of just going with the clamps like I was originally going to do.

 

Right now your cat inlet is 2-1/4". The inlet to the 9118 is 3". You'll need an adapter fabricated to go from 2-1/4" to 3". Not a job you're likely to be able to do yourself.

 

alright thats exactly what I needed to know. Is there an adapter already made or will it have to be made? I know for my daily driver I just put a muffler on it and was able to buy an adapter for the muffler to fit the stock piping