HFC Rasp

joshs09slvrZ · 07-06-2012, 07:37 PM

What exactly causes it? I have Berk HFC/CBE and I get rasp when I really get on it...sounds like a fart can...

Chuck@Z1 · 07-09-2012, 03:43 PM

The HFC's sound different because they are allowing more flow and the 370Z is bad to become "raspy" but you can also check for an exhaust leak where it bolts to the header.

We have seen several cars (including our own) with this problem and came out with gaskets just for this purpose.

chrisbeltre · 07-09-2012, 04:46 PM

Chuck, which lip and side skirts are you running on that white Z? I like the way they look.

SS_Firehawk · 07-09-2012, 07:05 PM

Resonators help a lot.

Chuck@Z1 · 07-09-2012, 07:50 PM

Quote:

Originally Posted by chrisbeltre

Chuck, which lip and side skirts are you running on that white Z? I like the way they look.

The lip was a Nismo S-tune lip. It can be found Here.

The sideskirts are stock but the Advan wheels and coilover setup really help with the look.

joshs09slvrZ · 07-09-2012, 08:42 PM

Quote:

Originally Posted by Chuck@Z1

The HFC's sound different because they are allowing more flow and the 370Z is bad to become "raspy" but you can also check for an exhaust leak where it bolts to the header.

We have seen several cars (including our own) with this problem and came out with gaskets just for this purpose.

What exactly would I be looking for as far as a leak? Exhaust fumes coming out?

PaulZ370 · 07-09-2012, 08:51 PM

Quote:

Originally Posted by joshs09slvrZ

What exactly causes it? I have Berk HFC/CBE and I get rasp when I really get on it...sounds like a fart can...

If you ever feel like changing the exhaust because of the Rasp, then I'd strongly suggest Fast Intentions Resonated HFC's with the 18" Resonated CBE. Absolutely no Rasp, Absolutely no Drone, and a very powerful low rumble at idle and a throaty roar at acceleration. I have mine with K&N Short Ram Intakes which contribute to the growl at acceleration. I have seen people drive up to the side of me and roll their windows down to listen, with lots of compliments from everyone that hears it.

Highwind · 07-09-2012, 10:11 PM

Quote:

Originally Posted by PaulZ370

If you ever feel like changing the exhaust because of the Rasp, then I'd strongly suggest Fast Intentions Resonated HFC's with the 18" Resonated CBE. Absolutely no Rasp, Absolutely no Drone, and a very powerful low rumble at idle and a throaty roar at acceleration. I have mine with K&N Short Ram Intakes which contribute to the growl at acceleration. I have seen people drive up to the side of me and roll their windows down to listen, with lots of compliments from everyone that hears it.

Detailed Video or this is a lie.

djtodd · 07-09-2012, 10:25 PM

Quote:

Originally Posted by Highwind

Detailed Video or this is a lie.

lol

chrisbeltre · 07-09-2012, 10:27 PM

Nice highwind, that was funny.

andre12031948 · 07-09-2012, 10:37 PM

I believe it's because CATS have much more material to them cause they surve a purpose/job like clean up the toxic stuff produced by combustion. HFC's are mostly thin, mostly straight through, so that ruspy combustion noise is no longer kept in check. Something like that.

Try running car without the exhaust system from HFC back. After a couple of days, put the exhaust system back up. The car now will sound much better.

PaulZ370 · 07-10-2012, 10:16 PM

Quote:

Originally Posted by Highwind

Detailed Video or this is a lie.

LOL... Believe what you will. I have no inclination to prove anything to you.

joshs09slvrZ · 07-11-2012, 08:00 AM

It's not so much that the rasp bothers me because it's only at WOT...I guess I'm just more concerned that something was wrong with it. If it's normal...then I'm not going to worry about it anymore. I love the way Berk sounds!!

Highwind · 07-11-2012, 12:00 PM

Quote:

Originally Posted by chrisbeltre

Nice highwind, that was funny.

Not calling you out or anything. Just would be nice to have some more reference on these for the community. A simple Iphone video would do, im sure you want to show off your $2000+ dollar exhaust setup.

ben1620 · 07-11-2012, 04:26 PM

I just went through the same thing. The rasp was normal but I wasn't expecting it. The motordyne XYZ Y pipe will get rid of it. I installed mine last night and it is perfect. It gets rid of the "bumblebee in a can" sounds.

07-06-2012, 07:37 PM	#1 (permalink)
joshs09slvrZ Track Member Join Date: May 2010 Location: Spring Hill, FL Posts: 547 Drives: 09 7AT 370Z Rep Power: 16	HFC Rasp What exactly causes it? I have Berk HFC/CBE and I get rasp when I really get on it...sounds like a fart can... __________________ Stillen Gen3 CAI\|Berk HFC and CBE\|UpRev\|15mm H&R front spacers\|20mm Ichiba rear spacers\|Stillen front and rear sway bars\|Yokohama S. Drives\|Swift springs\|JDM Blinking Fog\|8000k HIDs\|9% window tinting, 47% on full windshield

07-09-2012, 07:05 PM	#4 (permalink)
SS_Firehawk Premium Member Join Date: Oct 2011 Location: Tampa Posts: 4,142 Drives: 13' Magma Red Nismo Rep Power: 7335	Resonators help a lot. __________________ Old Car:GTM TSC'd 550whp / 410lbft tq @ 11.88PSI New Car: Under Construction

07-09-2012, 10:37 PM	#11 (permalink)
andre12031948 Banned Join Date: Feb 2011 Location: monticello new york 127 Posts: 1,095 Drives: 08 350z black 6m/t Rep Power: 0	I believe it's because CATS have much more material to them cause they surve a purpose/job like clean up the toxic stuff produced by combustion. HFC's are mostly thin, mostly straight through, so that ruspy combustion noise is no longer kept in check. Something like that. Try running car without the exhaust system from HFC back. After a couple of days, put the exhaust system back up. The car now will sound much better. Last edited by andre12031948; 07-09-2012 at 10:40 PM.

07-11-2012, 08:00 AM	#13 (permalink)
joshs09slvrZ Track Member Join Date: May 2010 Location: Spring Hill, FL Posts: 547 Drives: 09 7AT 370Z Rep Power: 16	It's not so much that the rasp bothers me because it's only at WOT...I guess I'm just more concerned that something was wrong with it. If it's normal...then I'm not going to worry about it anymore. I love the way Berk sounds!! __________________ Stillen Gen3 CAI\|Berk HFC and CBE\|UpRev\|15mm H&R front spacers\|20mm Ichiba rear spacers\|Stillen front and rear sway bars\|Yokohama S. Drives\|Swift springs\|JDM Blinking Fog\|8000k HIDs\|9% window tinting, 47% on full windshield

07-11-2012, 04:26 PM	#15 (permalink)
ben1620 Base Member Join Date: Sep 2011 Location: Arkansas Posts: 191 Drives: '05 Denali '09 370z Rep Power: 14	I just went through the same thing. The rasp was normal but I wasn't expecting it. The motordyne XYZ Y pipe will get rid of it. I installed mine last night and it is perfect. It gets rid of the "bumblebee in a can" sounds. __________________ 09 Black 7AT Sport, UpRev, Koni, Swift, Whiteline, Motordyne XYZ, Stillen HFC/Exhaust, Stillen 25 row, Pioneer, Infinity

07-09-2012, 03:43 PM	#2 (permalink)
Chuck@Z1 Base Member Join Date: Jun 2010 Location: Carrollton Posts: 91 Drives: Varies Rep Power: 15	The HFC's sound different because they are allowing more flow and the 370Z is bad to become "raspy" but you can also check for an exhaust leak where it bolts to the header. We have seen several cars (including our own) with this problem and came out with gaskets just for this purpose.

07-09-2012, 04:46 PM	#3 (permalink)
chrisbeltre Base Member Join Date: Dec 2010 Location: El Paso Posts: 123 Drives: 10-White 370Z Sport Rep Power: 14	Chuck, which lip and side skirts are you running on that white Z? I like the way they look.

07-09-2012, 10:27 PM	#10 (permalink)
chrisbeltre Base Member Join Date: Dec 2010 Location: El Paso Posts: 123 Drives: 10-White 370Z Sport Rep Power: 14	Nice highwind, that was funny.

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