Ok so I have a 97 Ram 1500 4x4. I am doing a 3in exhaust.

Am I going to have to change my piping before the cat to make it a 3in? or is there a direct fit 3in cat?

Man I hate these dam small sizes [8D]

 

TTT

 

should be 2" in cat then you gotta make it 3" out dont recall cat being 3" out i had to use a expander from 2.5" to 3" out

 

Your cat should be dual in, single out, so unless your changing the y-pipe, you 3" will start after the cat.
I think I lost a little low end when I did 3" from the cat out. Noitcable improvements at high RPMs though.

 

ihad dual 2.5" inlets and 3" outlet on my high flo cat

 

Thanks for the help..the y pipe is where silver _dodge?

before the cat isn't it? can I change that to a 3in?