catalytic coverters question.

[CopMagnet5oh]

car made say about 300 rwhp with longtubes - off road H, and catback all 2.5 inch and then if i put the crappiest cheapest cats on, brand new tho. how much power can i lose.

the reason i'm asking is cause i just did that but the cats i got are good ones ( or so i was told ) dynomax i think, and i can feel that i lost some power up top, just wondering what is the worst # of hp i lost ?

thanks, i hope you can help.

- Kons

 

[HoofnIt]

From what I've read in all of the rags, high-flow cats don't hurt performance much, if at all. I don't have dyno numbers to back that up.

 

[saxman9801]

how much did the high flow cats alter the sound when you added them? I am putting two high flow cats in soon instead of the off road pipe, just don't want to lose the throaty sound. Dan

 

[89MustangGX]

I've had a coupel different exhaust setups on different cars over the years. I found the Bassani cats seemed to really quiet down the exhaust while the BBKs did almost nothign to quiet them down. I also found no noticible pwoer difference between them and offroad versions, even with better than 300hp.