lilmike81888

if i just cut out my cat and run a straight pipe will my car loose hp? idk if i let the exhaust have more flow if it will loose the presser it needs to put power out

Mrmoose

if its a turbo, not really going to lose any power, probably help. But removing the cats, its highly illegal just so you know.

lilmike81888

sorry its not a turbo and its a 90 so its pre emmisions

Mrmoose

Emissions have nothing to do with it, cats ARE required on ALL cars unless its pre 1975

WildmaN

Actually, 1975 and newer in non California states. I know first hand, because they failed me with my '75 Firebird without having cats on it. And when I called the state on it. They said '75 was the first year they put them on. And I said "lucky me!" lol

My mistake, I misread your post. I apologize. I didn't realize you said pre '75.

domsgarage

Theres a whole post on backpressure and gains and ****. Search for it. I think its a a sticky.