Nissan 370Z Forum  

Hi-Flow Cats too loud!

Originally Posted by 2fast4thelaw I loved the sound of the Stillen exhaust from the clips I heard. The HFC's radically change the exhaust note. I am not changing out my

Go Back   Nissan 370Z Forum > Nissan 370Z Tech Area > Engine & Drivetrain > Intake/Exhaust


Reply
 
LinkBack Thread Tools Display Modes
Old 08-21-2009, 02:53 PM   #16 (permalink)
A True Z Fanatic
 
Modshack's Avatar
 
Join Date: Mar 2009
Location: Greenville NC
Posts: 2,883
Drives: 370Z Sport
Rep Power: 976
Modshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond reputeModshack has a reputation beyond repute
Default

Quote:
Originally Posted by 2fast4thelaw View Post
I loved the sound of the Stillen exhaust from the clips I heard. The HFC's radically change the exhaust note. I am not changing out my exhaust system, thats like throwing the baby out with the bath water. I am just not happy with the HFC's It makes the car sound ricy. Plus I doubt I will pass emissions when I have to test car in the next 3 years with the HFC's. Plus I dont like the hiss the HFC's make. It makes it sound like I have an exhaust leak. I think my HFC's need to go.
Yours and similar posts have pretty much convinced me to leave the CATS alone. I think the Stillen is a tad quiet, but is a comfortable system when traveling with no bad characteristics. I'd be kicking myself if I made the change and then did not like it...
__________________

Steal my car! (SOLD)...Now Porsche Cayman S
Oil Cooler DIY: Here!
Modshack is offline   Reply With Quote
Old 08-21-2009, 02:54 PM   #17 (permalink)
Track Member
 
WShade's Avatar
 
Join Date: Jan 2009
Location: San Antonio, TX
Posts: 765
Drives: 09 370Z T/S/N
Rep Power: 187
WShade has a reputation beyond reputeWShade has a reputation beyond reputeWShade has a reputation beyond reputeWShade has a reputation beyond reputeWShade has a reputation beyond reputeWShade has a reputation beyond reputeWShade has a reputation beyond reputeWShade has a reputation beyond reputeWShade has a reputation beyond reputeWShade has a reputation beyond reputeWShade has a reputation beyond repute
Default

"mattkim85" in CA already got pulled over for his being to loud. Check the classifieds.
__________________
Q50S
Q60 RS400
WShade is offline   Reply With Quote
Old 08-21-2009, 03:32 PM   #18 (permalink)
JB1
Track Member
 
JB1's Avatar
 
Join Date: Mar 2009
Location: Chicagoland
Posts: 748
Drives: 09 Nissan 370Z sold
Rep Power: 17
JB1 has a spectacular aura aboutJB1 has a spectacular aura about
Default

What about stock exhaust en HFC's? That is the setup I am going for. From the video's DDM posted, it sounds good, not too loud and it should yield nice performance gains.
JB1 is offline   Reply With Quote
Old 08-21-2009, 03:56 PM   #19 (permalink)
6MT
A True Z Fanatic
 
6MT's Avatar
 
Join Date: May 2009
Location: ITU Zone 2
Posts: 22,459
Drives: Reliant Robin
Rep Power: 1789
6MT has a reputation beyond repute6MT has a reputation beyond repute6MT has a reputation beyond repute6MT has a reputation beyond repute6MT has a reputation beyond repute6MT has a reputation beyond repute6MT has a reputation beyond repute6MT has a reputation beyond repute6MT has a reputation beyond repute6MT has a reputation beyond repute6MT has a reputation beyond repute
Default

Quote:
Originally Posted by Modshack View Post
Yours and similar posts have pretty much convinced me to leave the CATS alone. I think the Stillen is a tad quiet, but is a comfortable system when traveling with no bad characteristics. I'd be kicking myself if I made the change and then did not like it...
I must say by reading all the negative posts here, that I'm kind of disappointed. A lot of people (by far the majority) talk about "modding" their cars. With just a little (and I mean a small amount) of research, one can find out loads about what the different mods will accomplish.

I was the same way. Some pointed questions, a little research, and finally... the big decision was made.



Nah, I've decided not to continue. I'll get flamed too hard.

So people..... my experience was to do the Stillen HFC's, CBE, Gen II intake system, and sway bars. I was surprised with the sound's "loudness". Yes, it's not quiet. But the performance gained far out weighs the "inconvenience" of the sound. I really like it. For those of you who are having trouble with the authorities, all I can say is I feel for you. Where I live, there's no such bother when we've got Harley's and the like driving around with what sounds like no exhaust at all.... the 370 sounds as quiet as a Honda Fit.

The HFC's (and the whole exhaust system) "resonate" at different revs. Cold starts are LOUD. Some speeds (read: revs) are uncomfortable (read: droning). But, I took a four day trip with the car and was very surprised at the level of comfort (sound wise). The audio system would generally cover up any exhaust notes when I wanted it to. After that, the rolled-up windows did wonders.

__________________
Andrew

2009 370Z Sport/Touring 6MT sold
2013 Honda Civic Si coupe D/D
6MT is offline   Reply With Quote
Old 08-21-2009, 05:55 PM   #20 (permalink)
Base Member
 
Join Date: May 2009
Location: Nashua NH
Posts: 178
Drives: 09 370Z BLk GTM TT
Rep Power: 15
blackbird is on a distinguished road
Default

I have the Stillen CBE, HFC, Headers, Gen 3 intake. car sounds like a Z. Cruising at 3000-3500 RPMS, sound is not harsh. Easy having conversations etc. In the hurry-up mode, it has a distinct throaty sound. Course this is comparing to just the Stillen exhaust since I had them install on day 3 of owning the car. Happy driver and local Law types have not stopped me. But this is Live Free or Die country. Or it could be I'm losing my hearing, but who cares.
blackbird is offline   Reply With Quote
Old 08-21-2009, 08:32 PM   #21 (permalink)
A True Z Fanatic
 
Minicobra1's Avatar
 
Join Date: Nov 2008
Location: Orange County, CA.
Posts: 1,205
Drives: 370Z Tour, Spt, 6mt
Rep Power: 644
Minicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond repute
Default

Quote:
Originally Posted by CrownR426 View Post
I wonder if cops look at these launches and try to find out where it is.
lol, hope none of us get caught!
Hope not That was in a very deserted industrial business park on a Sunday, I looked for a place with no cross streets and on a cul-de-sac. Not saying that this is a safe thing to do on the street, but I did put some thought into it.
I've seen others shooting video, and it looks like there right in front of their house in a residential section
Try and be as safe as possible out there and use discretion.
__________________
370z Tour| Spt Pack|Navi|BERK CBE|Berk HFC's| Eibach Springs| Hotchkis Sway Bars|SPC Camber Arms|15mm Ichiba Wheel Spacers| 19"Factory Nismo Wheels-Matt Black|Stop Tech Rotors|TWM Shifter|3M Tint|Black Fangs|Black Rear Valance|JDM Fog Light| MY BAND-www.myspace.com/petroleum
Minicobra1 is offline   Reply With Quote
Old 08-21-2009, 08:39 PM   #22 (permalink)
A True Z Fanatic
 
Minicobra1's Avatar
 
Join Date: Nov 2008
Location: Orange County, CA.
Posts: 1,205
Drives: 370Z Tour, Spt, 6mt
Rep Power: 644
Minicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond reputeMinicobra1 has a reputation beyond repute
Default

I think the Berks sound great, probably not quite as loud as the Stillen/Berk combo.
I've got Nismo/Berk at the moment, and it's a little too mild for me. Sounds great when you get on it, but I don't want to have to drive my car fast all the time to get the enjoyment of the engine growl. On the other hand, I don't want something that is going to drone or attract too much negative attention. Hoping the Berks CBE will be the solution. I don't want to give up my Berk HFC's they have definitely made the biggest difference in performance gains so far.
__________________
370z Tour| Spt Pack|Navi|BERK CBE|Berk HFC's| Eibach Springs| Hotchkis Sway Bars|SPC Camber Arms|15mm Ichiba Wheel Spacers| 19"Factory Nismo Wheels-Matt Black|Stop Tech Rotors|TWM Shifter|3M Tint|Black Fangs|Black Rear Valance|JDM Fog Light| MY BAND-www.myspace.com/petroleum

Last edited by Minicobra1; 08-21-2009 at 08:42 PM.
Minicobra1 is offline   Reply With Quote
Old 08-21-2009, 10:31 PM   #23 (permalink)
A True Z Fanatic
 
One_Quick_Z's Avatar
 
Join Date: May 2009
Location: Seneca Il
Posts: 1,374
Drives: 10 Civic EX Sedan
Rep Power: 218
One_Quick_Z has a reputation beyond reputeOne_Quick_Z has a reputation beyond reputeOne_Quick_Z has a reputation beyond reputeOne_Quick_Z has a reputation beyond reputeOne_Quick_Z has a reputation beyond reputeOne_Quick_Z has a reputation beyond reputeOne_Quick_Z has a reputation beyond reputeOne_Quick_Z has a reputation beyond reputeOne_Quick_Z has a reputation beyond reputeOne_Quick_Z has a reputation beyond reputeOne_Quick_Z has a reputation beyond repute
Default

I like the loudness under WOT that is why Im going to get Test Pipes when I get Exhaust

I loved the sound of my Borla With APS test pipes, Megan Racing Headers on my 06 350Z


DAN
__________________
-My BRZ with exhaust will decimate all if we overnight parts from Japan-

10 Civic EX Sedan- Current Daily
One_Quick_Z is offline   Reply With Quote
Old 08-21-2009, 10:37 PM   #24 (permalink)
Base Member
 
Join Date: Jun 2009
Location: north carolina
Posts: 45
Drives: 2003 cobra, 2006 tb
Rep Power: 15
tstrick9 is on a distinguished road
Default

I thought it was against federal law to removing functioning cats even if they were replaced with other cats.
tstrick9 is offline   Reply With Quote
Old 08-21-2009, 10:37 PM   #25 (permalink)
A True Z Fanatic
 
m4a1mustang's Avatar
 
Join Date: Feb 2009
Location: Northern VA
Posts: 55,385
Drives: on two wheels
Rep Power: 6962
m4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond reputem4a1mustang has a reputation beyond repute
Default

Quote:
Originally Posted by Modshack View Post
Yours and similar posts have pretty much convinced me to leave the CATS alone. I think the Stillen is a tad quiet, but is a comfortable system when traveling with no bad characteristics. I'd be kicking myself if I made the change and then did not like it...
Same for me... for now, anyways. I ordered the FI CBE with 18" resonators, which I'm thinking will be loud enough for me. If not, maybe I'll add HFCs... but only if I'm sure it won't be obnoxious.
__________________
- Steve
MAZOC Meet Thread
Zs & Coffee - Saturdays at 10AM in Fairfax, VA and Columbia, MD (Click the banner!)
LIKE us on Facebook!
m4a1mustang is offline   Reply With Quote
Old 08-22-2009, 10:57 AM   #26 (permalink)
Enthusiast Member
 
2fast4thelaw's Avatar
 
Join Date: Feb 2009
Location: Denver Co
Age: 49
Posts: 403
Drives: 09 370Z Sport/MT6
Rep Power: 16
2fast4thelaw will become famous soon enough
Default

HFC will not make it obnoxiously loud unless you are WOT all the time. If you drive normal speed limit and keep your revs under 3k it's not that loud.

The HFC definitly make the car sound modified and that is what I didnt really want. Its not a bad sound by any means, it just isnt refined like the exhaust note of like a Porche or something. It sounds like a tuner.

Now I would tell anyone who is considering test pipes it will border on the obnoxious loud side and will sound raspy. Even with the HFC's there is a little rasp at WOT but test pipes would amplify this.

Last edited by 2fast4thelaw; 08-22-2009 at 11:00 AM.
2fast4thelaw is offline   Reply With Quote
Old 08-22-2009, 08:30 PM   #27 (permalink)
Base Member
 
Join Date: Jan 2009
Location: new mexico
Posts: 141
Drives: 2007 335i coupe
Rep Power: 283
john370z has a reputation beyond reputejohn370z has a reputation beyond reputejohn370z has a reputation beyond reputejohn370z has a reputation beyond reputejohn370z has a reputation beyond reputejohn370z has a reputation beyond reputejohn370z has a reputation beyond reputejohn370z has a reputation beyond reputejohn370z has a reputation beyond reputejohn370z has a reputation beyond reputejohn370z has a reputation beyond repute
Default

OK OK OK.. I did it today! I took off the Berk HFC's!

Oh my God!

I love my car again!!!!!

It sounds about 75% less noisy.
100% less raspy!
100% less drone!
and still has a sporty sound at the upper rpm range.

To be honest, I drove home with a smile on my face the entire drive home from the exhaust shop, and that's the first time that's happened.

If anyone is one the fence on this one. I hope this pushes you in one way.

Good luck to all!
__________________
2009 370Z, Had Berk HFC and un-installed them cuz too noisy!, Stillen CBE, 10mm rear wheel spacer, K&N drop in filters. Blower to come...
john370z is offline   Reply With Quote
Old 08-29-2009, 10:50 PM   #28 (permalink)
Enthusiast Member
 
2fast4thelaw's Avatar
 
Join Date: Feb 2009
Location: Denver Co
Age: 49
Posts: 403
Drives: 09 370Z Sport/MT6
Rep Power: 16
2fast4thelaw will become famous soon enough
Default

I havent pulled my cats yet and I may not. I just got my car back from the car audio shop and they put 120 sq ft of sound deadning in the car and it is sooo quiet inside. I can't hear the anoying drone anymore. Its a night and day difference not to mention hardly any road noise now.

I can live with HFC now. Without the sound deadning, I was ready to yank them like "John370z"
2fast4thelaw is offline   Reply With Quote
Old 08-30-2009, 12:07 AM   #29 (permalink)
Base Member
 
Join Date: May 2009
Location: NRH2O, Texas
Posts: 32
Drives: 09 370Z MB 7AT
Rep Power: 15
MacDaddy is on a distinguished road
Default

2Fast, not to get off thread but other than the doors, where did the shop install the material...I'm guessing dynamat??? Fixin to do mine

thanks

mac
MacDaddy is offline   Reply With Quote
Old 08-30-2009, 01:54 AM   #30 (permalink)
Enthusiast Member
 
2fast4thelaw's Avatar
 
Join Date: Feb 2009
Location: Denver Co
Age: 49
Posts: 403
Drives: 09 370Z Sport/MT6
Rep Power: 16
2fast4thelaw will become famous soon enough
Default

Actually I used Rammat. Its not only cheaper but its better. I bought 2 rolls which are 62.5 sqft for about a $100.00 a roll. Plus I bought 6 yards of ensolite foam barrier that is glued to the Rammat.

RAAMaudio

I had it applied double layer in the trunk floor and wheel wells and yes, both doors. It was very well worth it as the car is amazingly quiet inside.

I had the entire interior of the car removed. I am adding pictures of the process on the Audio thread but there are a few there already.
2fast4thelaw is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Berks vs AAM High flow cats? zulus370Z Intake/Exhaust 28 12-09-2015 12:45 AM
AAM Competition High Flow Cats Rob@Altered Group Buys 3 12-03-2009 02:04 PM
High Flow Cats and Y-Pipe DNadar Intake/Exhaust 0 06-11-2009 04:44 PM


All times are GMT -5. The time now is 03:37 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0 PL2