I live in Oregon and don't want to get busted for not having a cat. I also am getting kind of sick of the exhaust fumes. So, I am going to have my Catco HFC installed fairly soon. Will this make my exhaust any quieter or should I get a resonator as well? Thanks!

 

yes, it will make it quieter

 

Is it a significant difference?

 

I thought a 3inch HFC made my car a good bit quieter, i like it a lot better now for cruising around town and longer trips. I also added the QTP cutout DP before the cat so i can whip that open for some extra power.

 

Thanks for the input

 

I have the AMS TBE with there 3 inch HFC. IT sounds good but is still quite a bit louder then stock. I haven't had any noise problems though.

 

Have the Tanabe exhaust and the HFC is quieter than the test pipe, but still louder than the stock cat.

 

Is there any general rule of thumb as to how much power a HFC robs?

I too wouldn't mind a quieter ride, but don't want to sacrifice TOO much power...

 

I've heard to as much as 20hp if you have quite a few mods.

 

I have read between 3-15 hp, depending on the type of power you are making.

 

there have been dynos on stage 1-2 cars (around 320whp) losing about 10whp from a test pipe to a HFC.

-Chris