So I came into some money and I've decided to mod my z. One of the mods was some berk HFCs, but it seems that when paired with an exhaust it hisses. Or better put it becomes raspy. Is there anyway around this without having to keep to my stock cats?

 

For clarification (fast forward to 35 seconds)

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nope, sounds normal to me.

(btw, the dude sitting down with his legs crossed behind u could've held the camera for you)

 

Really you don't hear that hissing sound after he revs?

(btw this isn't my video )

 

I hear something funny. There's a hissing sound just before the revs die down. That doesn't sound normal.

 

My single hisses since I got test pipes. No exhaust leaks either. I would say its pretty normal.

 

But is there anyway to get ride of it? It doesn't sound clean to me.

 

every car ive heard with similar setups to ur (including mine) hisses. pretty normal. creating more backpressure in your exhaust system is a good way to get rid of it (ie put your stock cats back on)

 

sounds normal to me....i wouldn't worry about it

 

Alright I'll just keep my stock cats on. Thanks guys!

 

No.

 

yes

 

i have it on mine to. i took it to my machanic and he said it the heat shield in the drive shaft :/.

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I don't about the heat shield, but because of that sound im having second thoughts about purchasing those HFCs.

 

well see the sound i have doesnt come from were my Test pipes are out it comes from the area of axle. The end of the shaft tunnel.

 

Could be, but let me ask you something. Does it Bother you in anyway? Is it noticeable when driving or in cabin?

 

lol eh not really but when i do hear it im like "o it my bov going of from some small boost " lol i guess it a personal thing and frankly i usually got the sound system going so i rarely hear it lol.

 

Mine is definitely noticeable but at the same time I really don't give a **** about a little hissing noise lol

 

dude... u probably don't want to be modding your Z if you're worried about a negligible, normal hissing due to hfc/test pipes.

 

that will happen sometimes when the cats goin into the y pipe or h pipe are diff sizes just a resonation that happens. alot of people have it