kodeydg

im looking at removing mt blown out leaky cat, im lucky i dont have to deal with e-tests so it doesnt matter, but it sounds like crap, and looks worse, im looking at building a pipe from the headers to a flowmaster, but i need a y pipe collector to go back to a single pipe, so i need to know what the pipe diameter is going into the cat on (94) 5.0 f150, i usied a measuring tape, but that didnt help, and i dont have a big enough caliper. any way any idea? i think its 2 1/4, but id like a real number, any help, thanks

Crownman

It's 2.25. I say if you're going to replace that much pipe then just replace it all from the manifold back with 2.5. It won't cost much more at all.

kodeydg

thats the plan, im going to go to 2.5 from where the pipe goes into the cat, back. i have a 2nd motor the i plan on building, giving my truck a little power, and im going to put some headers on it, so ill have to mod the pipe again later but for now this will do thanks

kodeydg

what do you think of 3" pipe without a tune, i plan on one day installing a quarter horse but until then, do you think it'll be to big with a stock map ? i know itll sounds nice but i know theres more to it then sound. any ideas ?

Crownman

Going 3 inch is a.waste. 2.5 is plenty big enough. Look at it this way, 400hp at the rear wheels is on the edge of the strength of a stock 302/351 block. A 2.5 in exhaust will support much more than that just fine. So dont bother with 3 in.