Welcome to 911UK
The only place for Porsche, 911uk is the definitive enthusiast and resource site for the Porsche 911.
Registration is fast, simple and absolutely free, so join up today for full access to the site and benefit from latest member offers.

Porsche Classifieds
Porsche Buyers Guides
Sell Your Porsche on 911uk
Create a Free Classified Advert
Search Ads
Classified Adverts FAQ
Trade Classified Information
Buyer & Seller Fraud Protection
Pre Purchase Inspection (PPI)
Porsche Car Sourcing
Porsche Cars Wanted
Model
Stock
Porsche 911
991 : 2011- 8
997 : 2004- 67
996 : 1997-2005 43
993 : 1993-1998 10
964 : 1989-1993 5
Carrera 3.2 : 1983-1989 1
Carrera SC : 1977-1983 0
930 Turbo : 1975-1989 0
Early 911 : 1964-1977 2
Porsche Other Models
Classic : 1950-1965 1
Boxster : 1997- 14
Cayman : 2005- 13
Cayenne : 2003- 10
Macan : 2014- 2
Panamera : 2009- 3
912-914-924-928-944-968 4
959 - CarreraGT - RaceCar 1
Car Parts For Sale & Wanted
Other Items For Sale & Wanted
Wheels Tyres For Sale & Wanted
Number Plates For Sale Wanted

Porsche Services
Porsche Body Shop Repair
Paint Protection & Body Wrapping
Porsche Classic Insurance
Porsche Classic Parts
Porsche Classic Restoration
Porsche Design Collection
Porsche Engine Gearbox Rebuild
Porsche Heritage & History
Porsche News
Porsche Picture Gallery
Win a New Porsche 911

Porsche Parts
Body Parts, Body Styling
Brakes, Clearance
Electrical, Exhausts
Engine Cooling, Engine Electrical
Engine Rebuild, Heating Cooling
Interior Incar, Lighting
Rubber Seals, Service Parts
Steering, Suspension
Transmission, Workshop Tools
Early 911, 911 - 930, 928 - 968
964 - 993, 996 - 997, Boxster
Cayman, Cayenne, Panamera

Porsche Model Range
911 [991] 2011-Current
Porsche 911 [991]
911 [997] 2004-Current
Porsche 911 [997]
911 [GT] GT1-GT2-GT3
Porsche 911 [GT]
911 [996] 1997-2005
Porsche 911 [996]
911 [993] 1993-1998
Porsche 911 [993]
911 [RS] RS-RSR
Porsche 911 [RS]
911 [964] 1989-1993
Porsche 911 [964]
911 3.2 1983-1989
Porsche 911 3.2 Carrera
911 SC 1977-1983
Porsche 911 SC
911 [Early] 1964-1977
Porsche 911 [Early]
Boxster & Cayman
Porsche Boxster & Cayman
Cayenne & Panamera
Porsche Cayenne & Panamera

911uk Site Partners

Post new topic   Reply to topic
Author Message
ditchvisitor
Newbie


Joined: 09 Oct 2017
Posts: 37
Location: Oxfordshire


PostPosted: Sun Oct 29, 2017 12:21 pm    Post subject: 996 GT3 Cat bypass Reply with quote

I've made the mistake of hearing what a 996 GT3 sounds like with cat bypass pipes fitted and am looking around to see what is available.
Does anyone have any sat around that they aren't using, or recommend which ones to get?
_________________
"Try to stay in the middle of the air, do not go near the edges of it. The edges of air can be recognised by the appearance of ground, buildings, sea, trees and interstellar space. It is much more difficult to fly there!!"
 
  
View user's profile Send private message
   
kingston
Österreich


Joined: 09 Jun 2010
Posts: 913



PostPosted: Mon Oct 30, 2017 8:05 am    Post subject: Reply with quote

Where did you hear that?

I've had straight out from cat which sounded awesome but you get a noticeable drop in low down torque but get it back at the top end. Which is great for a few months but then frustrating
_________________
I really must learn to spell check and proof read my posts Smile
 
  
View user's profile Send private message
   
NLW73
Österreich


Joined: 27 May 2014
Posts: 900
Location: Yateley


PostPosted: Mon Oct 30, 2017 9:01 am    Post subject: Reply with quote

seconded. if its a road and occasional track car then don't bother. low end it will be rather gutless.

if a race car and you are spending your time at the top end then great. and get it mapped for that

according to Wayne Schofield (Chip wizards) who knows a lot about tuning NA cars he said don't bother for road going GT3s.

the OEM GT3 exhaust system is heavily optimised for exhaust gas scavenging according to wayne and changing this really does play around with how the engine reacts and then drives.

maybe look at 200 CELL cats at best? and then get it re mapped with the IPD plenum and 997 GT3 bigger throttle body?
_________________
996 GT3 mk2 - Guards Red
 
  
View user's profile Send private message
   
ditchvisitor
Newbie


Joined: 09 Oct 2017
Posts: 37
Location: Oxfordshire


PostPosted: Tue Nov 21, 2017 6:10 pm    Post subject: Reply with quote

https://youtu.be/JOCPwHdS-5E

This video! I was more concerned about it making a bit more noise more than anything else, it's recently had new OEM mufflers etc
_________________
"Try to stay in the middle of the air, do not go near the edges of it. The edges of air can be recognised by the appearance of ground, buildings, sea, trees and interstellar space. It is much more difficult to fly there!!"
 
  
View user's profile Send private message
   
NLW73
Österreich


Joined: 27 May 2014
Posts: 900
Location: Yateley


PostPosted: Tue Nov 21, 2017 9:17 pm    Post subject: Reply with quote

it would be so noisy it would drive you up the wall. and your neighbours.

I had this on mine when I first bought it....it had no low down torque and everyone hated me due to the noise.

forget track days too.

you could go 200 cell or 100 cell cats. do you have sports boxes too? if you are oem exhaust they can be quiet ish.
_________________
996 GT3 mk2 - Guards Red
 
  
View user's profile Send private message
   
ditchvisitor
Newbie


Joined: 09 Oct 2017
Posts: 37
Location: Oxfordshire


PostPosted: Tue Nov 21, 2017 9:21 pm    Post subject: Reply with quote

NLW73 wrote:
do you have sports boxes too?


I'm pretty sure it's a standard system, was there an option of a sports exhaust from new?
_________________
"Try to stay in the middle of the air, do not go near the edges of it. The edges of air can be recognised by the appearance of ground, buildings, sea, trees and interstellar space. It is much more difficult to fly there!!"
 
  
View user's profile Send private message
   
NLW73
Österreich


Joined: 27 May 2014
Posts: 900
Location: Yateley


PostPosted: Tue Nov 21, 2017 10:22 pm    Post subject: Reply with quote

not sure. few after market options.

some decent fabricators out there who can make sports back boxes for you which will have a better sound and flow. maybe 200 cell cats too?

will certainly help with noise and flow but not be bonkers loud.

I used Viper Exhausts in Essex and run by former F1 exhaust fabricator.

i think Top gear exhaust do a full system with headers for a Gt3.
_________________
996 GT3 mk2 - Guards Red
 
  
View user's profile Send private message
   
Daniel
Donnington
Donnington


Joined: 02 Feb 2005
Posts: 11905
Location: Not where I want to be!

2000 Porsche 996 GT3 Mk1

PostPosted: Wed Nov 22, 2017 11:41 am    Post subject: Reply with quote

I have a M+M Exhaust on my MK1 GT3.

M+M make exhaust's for Manthey and a few of the race teams.

great quality -

http://www.m-m-germany.de/

Thumb
_________________
*Current - GT3 996.1 Clubsport (Manthey K400)

EX VR993 - C4
EX 993 - C2
EX GT3 996.1
EX Cayman 3.4 S 987.1
EX Megane R26R #36.
EX Cayman R
 
  
View user's profile Send private message Send e-mail
   
Daniel
Donnington
Donnington


Joined: 02 Feb 2005
Posts: 11905
Location: Not where I want to be!

2000 Porsche 996 GT3 Mk1

PostPosted: Wed Nov 22, 2017 11:55 am    Post subject: Reply with quote

http://m-m-germany.de/wp-content/uploads/2015/03/996T_020_Datenblatt.pdf

How far do you want to go?

mufflers
Cats
full system

Thumb
_________________
*Current - GT3 996.1 Clubsport (Manthey K400)

EX VR993 - C4
EX 993 - C2
EX GT3 996.1
EX Cayman 3.4 S 987.1
EX Megane R26R #36.
EX Cayman R
 
  
View user's profile Send private message Send e-mail
   
Stuart
General
General


Joined: 16 Sep 2007
Posts: 5045
Location: Waterworld

2004 Porsche 996 GT3 Mk2

PostPosted: Wed Nov 22, 2017 6:38 pm    Post subject: Reply with quote

Ditto Dan, it's also a plus on resale. There are also some very good full systems in the US right now.
 
  
View user's profile Send private message
   
Cheburator
Trainee


Joined: 15 Aug 2014
Posts: 88



PostPosted: Mon Nov 27, 2017 1:44 pm    Post subject: Reply with quote

I have the MM full system on my K400 - 100 cell cats, equal length headers, the x-cross over and the sport boxes. I love it. Sounds lovely. I get thumbs up everywhere.

No chance to make it on to a track day though at Brands for example...

So be careful what you wish for...
_________________
Porsche 996.1 GT3 CS K400
Porsche 928 GTS 5-spd
Porsche 944 Turbo Cup race car
Porsche 928 Cup race car
Various BMWs
 
  
View user's profile Send private message
   
Slippydiff
Silverstone


Joined: 22 Nov 2007
Posts: 145



PostPosted: Wed Nov 29, 2017 12:12 am    Post subject: Reply with quote

Cheburator wrote:
I have the MM full system on my K400 - 100 cell cats, equal length headers, the x-cross over and the sport boxes. I love it. Sounds lovely. I get thumbs up everywhere.

No chance to make it on to a track day though at Brands for example...

So be careful what you wish for...


The early Manthey K400 exhaust systems differ from the latter iterations.
The early systems utilised Europipe silencers, X pipe and cats along with M&M manifolds. Once the wire wool wadding in the Euopipe silencers has decayed or been blown out, they sound simply epic :

https://m.youtube.com/watch?t=13s&v=w3J8HeIfJwc

The later systems utilized a complete M&M system (using pre-pressed silencer boxes as opposed to the fabricated Europipe items) The system on the yellow car linked to above would appear to have later M&M silencers (idendified by the straight cut tailpipes rather than the slash cut rolled edge Europipe items) though the yellow car sounds as if the silencers are completely devoid of their wadding ... ! ! !
 
  
View user's profile Send private message
   
Cheburator
Trainee


Joined: 15 Aug 2014
Posts: 88



PostPosted: Wed Nov 29, 2017 8:41 am    Post subject: Reply with quote

Slippydiff wrote:
Cheburator wrote:
I have the MM full system on my K400 - 100 cell cats, equal length headers, the x-cross over and the sport boxes. I love it. Sounds lovely. I get thumbs up everywhere.

No chance to make it on to a track day though at Brands for example...

So be careful what you wish for...


The early Manthey K400 exhaust systems differ from the latter iterations.
The early systems utilised Europipe silencers, X pipe and cats along with M&M manifolds. Once the wire wool wadding in the Euopipe silencers has decayed or been blown out, they sound simply epic :

https://m.youtube.com/watch?t=13s&v=w3J8HeIfJwc

The later systems utilized a complete M&M system (using pre-pressed silencer boxes as opposed to the fabricated Europipe items) The system on the yellow car linked to above would appear to have later M&M silencers (idendified by the straight cut tailpipes rather than the slash cut rolled edge Europipe items) though the yellow car sounds as if the silencers are completely devoid of their wadding ... ! ! !


I know the yellow car - remember it having a new rear left control arm being replaced at Ring-Racing after it had kissed the Armco.

Mine sounds about the same - allegedly 107db on drive-by at full chat at Brands (under the bridge into pilgrim's rise and just before druids)
_________________
Porsche 996.1 GT3 CS K400
Porsche 928 GTS 5-spd
Porsche 944 Turbo Cup race car
Porsche 928 Cup race car
Various BMWs
 
  
View user's profile Send private message
   
Slippydiff
Silverstone


Joined: 22 Nov 2007
Posts: 145



PostPosted: Wed Nov 29, 2017 12:13 pm    Post subject: Reply with quote

You’ll need patience, but here’s my Manthey K400 with early Europipe system out in the wilds of Wales, the final fly by at 4.00 onwards gives the best insight as to the true sound ... :

https://youtu.be/PeHWqBAt_rk
 
  
View user's profile Send private message
   
Display posts from previous:   
Post new topic   Reply to topic   All times are GMT - 12 Hours
Page 1 of 1

 
Jump to:  

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You can attach files in this forum
You can download files in this forum
You cannot post calendar events in this forum