Hissing noise from 370z aftermarket exhaust system
 

anyone experience hissing noise after installation of aftermarket catback exhaust.(low RPM usually when car just got to a stop light)

Yes, that is normal under deceleration of the motor

very normal.

Mine doesn't hiss...but maybe it will when I install my HFC's?

Certain X-pipe configurations cause the hiss. It will be amplified by the addition of HFCs, TPs, or LTHs.

I know with FI's X-pipe, even with stock cats, there's a good bit of hiss on decel in low RPMs. I don't think the H-pipe systems hiss, and I know that the systems without a crossover pipe have no hiss at all. ZCarMan and Tooohip both run HFCs with the AAM V1 CBE (no crossover) and their cars have zero hiss.

Steve, as long as your Berks use an X-pipe crossover you'll probably pick up an audible hiss once you install your HFCs.

Note: I used "hiss" in every sentence of this post.

Stillen CBE added a little hiss but after combining it with the ERZ HFCs the decel hissing got much more noticeable. Just a fact of life with this car.

It's just inherent to an X-pipe. H-pipes tend to sound "fuller" at lower RPMs vs. an X pipe, which sounds hollow. I used to run a off-road X pipe on my Mustang and there was a hiss-like sound from that at the low RPMs. Screamed like a banshee up top, though.

I like the hiss. :cool:

I hate it. :icon18:

It sounds so cheap.

I hated it at first, but i like it now :icon17:

FI Cat-Back No Resonaters... Bring on the HISS!!!!!!!!!!!!!!!!!

I went from stock to BERK HFC with stock exhaust, then added the Berk Exhaust (X-pipe) and now I'm back to stock cats and Berk exhaust. In my experience:

HFC = Hiss
HFC + x-pipe CBE = More hiss
Stock cats + X-pipe CBE = no (to me noticeable) hiss

All in all I like my current set up the best, nice added volume, no drone, no hiss.

Except the second sentence...

Damn! :icon18:

In my defense I could scramble some words in that sentence to spell "hiss." :D

It will be amplified by the addition of HFCs, TPs, or LTHs.

No you didnt.

Crap! I lose.