I have an 88' 4.2L yj all stock exhaust with a new cat. i welded on.
I can get a good deal from my friend for a new exhaust header but it turns in to a 3" pipe. My header i have now goes to a 2" pipe.
I was woundering if i can istall those headers and instead of running a 3" pipe all the way out and getting a new cat, if i can bring the pipe before the cat. to 2.5" then at the cat down to 2.25"?
would that work?
would it impove flow?
would their still be enough back pressure for the engine?
any advice of what i should do
--im looking to increase flow and mabey gain a little hoursepower at the same time