supadice

I just got FI RHFC and I get a hissing rasp sound when i accelerate hard especially before the car is fully warmed up. It doesn't happen all the time, i just want to know if its a normal sound associated with getting HFC. This video is cold start and revving to just under 2000 rpm. You can here the hiss as soon as it starts then dissipates after initial warm up of about 30 second. Then you can here the hiss when I'm holding revs. Had shop who installed check for leaks and found none, also had infiniti check for leaks, found none. The sound only comes from front of car where cats are. The sound coming out from the exhaust is deep and nice.

GOPR0513 - YouTube

muyrec

It's a normal sound that happens when you switch up the exhaust. That's the nature of our beautiful VQ engine. You only modded the hfc? Other people who installed their catbacks have the same sound. My invidia exhaust and invidia HFC does the same sound. It can be fixed by installing a resonated cross pipe. I know that the noise is coming from my cross pipe. I think for OEM application the noise will probably be coming from the Y-pipe/mid pipe connection.

supadice

I also have a FI non resonated cat back

ANMVQ

iTrader: (13)

Sounds exactly like mine did.

terribleone

I have Motordyne ART pipes and they sound the same way when the car is not warmed up.

im_g37_fast

Mine sounds the exact same way after my ark grip cat back install. I hate that sound! I want it to go away asap!!! I can hear it in my car when i idle. Please keep me updated! Post pics and videos on how or where to fix!

Nightfury37

Sorry for response on old thread. Has anyone figured out what the hiss is about? I have a 08 G37 Coupe , intakes, dc sport headers, motordyne art pipes, ark grip cbe and i also get this hiss. On cold start, and around 3k rpm when accelerating aswell as decel and i can faintly here it at idle. It seems very consistent too. I've checked for leaks, no leaks
, I've replaced the whole exhaust and still get it. Not sure what to do anymore and its really annoying. Makes the car sound like a pos. Someone said it could be the intakes but its pretty noticeable between intake whistling and the hiss from what I'm hearing. Any thoughts??