utap1

Legality aside-- Will removing my cats change the way my car runs? In a bad way or a good way? The engine is being rebuilt. going back with forged rods, pistons and headwork, and long tubes. Do the cats stay or go??

Timspony

For a litle extra HP, just go out & get a high-flow X or H pipe....I'm running a Bassani Catted X....

562cobra

cat-less, but don't do it the cheap way. Buy yourself a new midpipe, instead of removing stock ones and replacing it with straight pipes.

Mustang3GT07

When I do my LT's Im going to run a high flow catted x.

CobraBob

I just don't like to recommend a catless setup. Simply because it's not legal and if you get caught you have the hassle of swapping to a catted midpipe. I know a lot of people like to go catless. Some for the extra loudness. I recommend just going with a good midpipe, like the MRT H-pipe, Bassani X-pipe, Magnaflow X-pipe. Just to name 3. The MRT, by the way, has a different sound/tone. Maintains what I call the classic Mustang muscle sound. JMO.

Blackvenom01

well some places dont smog like here in columbus(thank god)...if you want catless get bassani x pipe for the fact that if for some reason you have to smog you can buy the bassani high flow cats and put the in...

N/A cars get alittle more horsepower without the cats cause of the less air restriction...since your building your engine it seems like you may be thinking supercharger in the future...being catless and sc doesnt give you an extra hp

last h and x do have different sounds...x is sharper bittier and the h is more full growl....youtube the setup before you decide

Blackvenom01

you have 4 cats and 2 go with the longtubes or new x/h pipe...