Notices

Impreza - Exhaust Too Loud!

Thread Tools
 
Search this Thread
 
Old 22 August 2014, 08:22 AM
  #1  
MrQaud
Scooby Regular
Thread Starter
 
MrQaud's Avatar
 
Join Date: Apr 2014
Location: Scotland
Posts: 82
Likes: 0
Received 0 Likes on 0 Posts
Default Impreza - Exhaust Too Loud!

Well had the impreza for a couple of weeks. Wife not to happy about how loud it is... Roger Clarke GT Spec equal length manifold, up-pipes Full Mongoose 3 inch, No Cats etc

Personally I like the sound but I can see the wife's point and I've noticed a few neighbours not looking too happy about it too.

It's a 2.1 engine with a lot of stuff done to it running around 420 bhp. What can I do to quieten it down a bit. I spoke to the previous owner and he said not to fit an exhaust bung (even if I could find one to fit the Mongoose 5 inch tail pipe as it would cause problems with the running of the car???

Anyone got any sensible suggestions on what I can do. If I were to replace the exhaust with a more silenced one, I'm guessing I'd loose power so that's not ideal...
Old 22 August 2014, 08:35 AM
  #2  
neil-h
Scooby Regular
 
neil-h's Avatar
 
Join Date: Apr 2013
Location: Berks
Posts: 4,224
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by MrQaud
Anyone got any sensible suggestions on what I can do. If I were to replace the exhaust with a more silenced one, I'm guessing I'd loose power so that's not ideal...
Not necessarily, fitting a decent sports cat will lower noise a bit without any significant drop in power. Same with a well designed silencer.
Old 22 August 2014, 08:53 AM
  #3  
MrQaud
Scooby Regular
Thread Starter
 
MrQaud's Avatar
 
Join Date: Apr 2014
Location: Scotland
Posts: 82
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by neil-h
Not necessarily, fitting a decent sports cat will lower noise a bit without any significant drop in power. Same with a well designed silencer.
Any suggestions on a quieter 3 inch bore rear silencer?
To be honest, I'd prefer something with a 4 inch tail pipe instead of the Mongoose 5 inch as it's a bit over the top...
Thanks.
Old 22 August 2014, 09:28 AM
  #4  
Cocker
Scooby Regular
iTrader: (3)
 
Cocker's Avatar
 
Join Date: May 2004
Location: Essex
Posts: 1,821
Likes: 0
Received 1 Like on 1 Post
Default

fit a revolution system, or a Milltek system. They are on the quieter side but still good for power
Old 22 August 2014, 09:41 AM
  #5  
MrQaud
Scooby Regular
Thread Starter
 
MrQaud's Avatar
 
Join Date: Apr 2014
Location: Scotland
Posts: 82
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by Cocker
fit a revolution system, or a Milltek system. They are on the quieter side but still good for power
Am I correct in my thinking that by switching to a different brand of exhaust, provided I keep to the same centre bore, I should be fine with the cars current state of tune and mapping?

Thanks
Old 22 August 2014, 12:57 PM
  #6  
neil-h
Scooby Regular
 
neil-h's Avatar
 
Join Date: Apr 2013
Location: Berks
Posts: 4,224
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by MrQaud
Am I correct in my thinking that by switching to a different brand of exhaust, provided I keep to the same centre bore, I should be fine with the cars current state of tune and mapping?

Thanks
Yup, you'll only really want to get the map checked if you put a cat in it.
Old 24 August 2014, 02:31 PM
  #7  
edsel
Scooby Regular
iTrader: (2)
 
edsel's Avatar
 
Join Date: Sep 2012
Location: Essex innit
Posts: 1,036
Received 1 Like on 1 Post
Default

Resonator boxes or lack of make the world of difference. I'm running full decat and a one piece fujitsubo giken system. It passes noise testing at track days, IRC 94db @ 5k rpm.
The build quality is excellent. One piece from the down pipe and an almost straight run with no bends towards the back box.. It still burbles and sets of the occasional car alarm but by subaru standards its quite civilised.


Trending Topics

Old 24 August 2014, 04:06 PM
  #8  
InTurbo
Scooby Regular
iTrader: (3)
 
InTurbo's Avatar
 
Join Date: Jan 2013
Location: Oxford
Posts: 739
Likes: 0
Received 0 Likes on 0 Posts
Default

I'm having the same problem. Previous owner Fitted a Cobra 3'' decat turbo back and it's crazy loud. I replaced the back box with a 3'' Milltek and that's helped quieten it down a fair bit but still to much for me. So I'm having a large centre resonator fitted next month to see if that helps.
Also had to rotate the exhaust flange to get the Milltek to fit as they don't want people using there exhaust with other systems.

Last edited by InTurbo; 24 August 2014 at 04:19 PM.
Old 24 August 2014, 06:41 PM
  #9  
MrQaud
Scooby Regular
Thread Starter
 
MrQaud's Avatar
 
Join Date: Apr 2014
Location: Scotland
Posts: 82
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by edsel
Resonator boxes or lack of make the world of difference. I'm running full decat and a one piece fujitsubo giken system. It passes noise testing at track days, IRC 94db @ 5k rpm.
The build quality is excellent. One piece from the down pipe and an almost straight run with no bends towards the back box.. It still burbles and sets of the occasional car alarm but by subaru standards its quite civilised.

Is that a 3 inch bore system?
How much do they cost and where do you get them from?
Thanks.
Old 24 August 2014, 08:40 PM
  #10  
edsel
Scooby Regular
iTrader: (2)
 
edsel's Avatar
 
Join Date: Sep 2012
Location: Essex innit
Posts: 1,036
Received 1 Like on 1 Post
Default

Not sure on the size I think it's 2.5 at the join until 3". I'll have a measure up tomorrow. They come up for sale second hand now and then. Never seen a new one for sale in the uk.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
shorty87
Full Cars Breaking For Spares
19
22 December 2015 11:59 AM
ALEXSTI
General Technical
5
28 September 2015 09:29 PM
alcazar
Non Scooby Related
37
27 September 2015 10:35 PM
neil-h
ScoobyNet General
6
27 September 2015 11:27 AM
Phil3822
ICE
3
26 September 2015 07:12 PM



Quick Reply: Impreza - Exhaust Too Loud!



All times are GMT +1. The time now is 03:16 PM.