Cats/No Cats
 

I hear stories all the time, "I took off my cats and man what a difference" or "I took em off and I didnt feel anything" Is there anyone on here with some hard evidence or some intelligent knowledge on this subject.
Ty
Jax

I got the flowtech x-pipe without cats three weeks ago, the car sounds alot better, but as far as proof of performance gains, my 1/4 mile times didnt drop any. Not to say this wouldnt help in the long run, with more mods, maybe it would make a differance... But like i said, i got no proof, just time slips.......

On a mildly modified street car there is only a few hp difference between running an h- or x-pipe with hi-flow cats vs. no cats, though both offer good gains over the choked up stock setup with 6 cats. On a racecar the difference is more noticeable. The main difference is in the sound and emissions legality.

I have Bassani X pipes w/ cats and cat back. I was told that the cats have very little restriction. I was also told that if I went without cats, the check engine light would come on and it would actually rob some power.

Cats
 

I used to run straight pipes sure it sounded cool but i could feel the top end power increase but i lost low end torque so when i put on high flow cats just 2 i felt like i had more bottom end power and the torque/horsepower felt more smoother and consistent:D

this is not from me directly but, my buddy has a 97gt he has a bbk off road h on it, he put his stock one back on for emissions, and just riding in the car you could tell a pretty big difference in power down low and up top. his check engine light does come on though. (he just took the bulb out, lol) i would recommend the off road.

If you live in an emission controlled area, it behooves you to get an X-H pipe with high flow cats. It only costs you a few HP on light to moderatly modded stangs (2-4rwhp), and it keeps you from messing with the stupid thing every time inspection time comes...