I'am not recommending running 2 1/2" with or withour a cat. I didnt want to put one on since the original one rotted away. If cats were cheap I may have put one on. With the cam and header it made a world of difference. I forgot to mention my is carb not FI.

James

 

I second that. 2.50" piping is a little large for the 22r. With the exception of the turbo model.

 

2.5" is too big, 2.25 is about the maximum you want to go. i've got a cherrybomb glasspack hooked up to my thorley header with a turndown on the end right past the cab, it's ungodly loud. sounds really, really good at an idle though.

i'll probably have a setup made at an exhaust shop with something like a flowmaster 50 or magnaflow. figures, i can rebuild an engine, tear apart a 3rd member and put it back together, but i can never seem to get exhaust right

 

Mine is 2 1/4 from the Thorley back and it is as big as I'll go.2 1/2 is almost too big for the 3.0.

 

i got the crappy pacesetter header to a high flow magnaflow cat out to 2.5 inch pipe with a vforce muffler. in the morning it sounds like a v8 at idle. i do race so i opted for the 2.5 inch

 

The v-force is a pretty good alternative to a flowmaster. It is basically the same deisgn as the original 40 series flowmasters.

There is another flowmaster knockoff called the v-flow that is identical to the 40 series flowmaster. When I say identical I mean it. Flowmaster use to have a manufacturing plant in Mexico to help on all of their orders. This is the site and same equipment that the v-flow mufflers are produced on so the mufflers are identical right down to the welds.

Just a fyi, flowmasters patent just ran out on the oiginal 40's a couple of months ago so you will start to see a lot more flowmaster knockoffs with the same design.