Exhaust size???
11 March 2011, 10:26 AM
#1
Scooby Regular
Thread Starter
iTrader: (9)
Join Date: Nov 2010
Location: Hertfordshire
Posts: 485
Likes: 0
Received 0 Likes
on
0 Posts
Exhaust size???
Hi all, recently got a 3"de-cat and fitted it soon as. Then noticed that the Hayward system from cat back is only 2.5" :-(
Spoke to a garage and they recommend a full 3" as they rekon its restrictive as is. Anyone agree with this, and if so, would there be any benefit to a 3" system??
Spoke to a garage and they recommend a full 3" as they rekon its restrictive as is. Anyone agree with this, and if so, would there be any benefit to a 3" system??
11 March 2011, 11:02 AM
#2
A lot of conjecture on this.
Some people advocate that a 2.5" is good for upto 400 or even 450bhp! Beyond this, it's worthwhile going to 3" to do away with any potential restriction.
I personally have a full genuine 3" system i.e. inc. all flanges/unions, as I didn't want to take any chances with a potential restriction, etc. But I'm 'only' running 342bhp at the moment though.
Some people advocate that a 2.5" is good for upto 400 or even 450bhp! Beyond this, it's worthwhile going to 3" to do away with any potential restriction.
I personally have a full genuine 3" system i.e. inc. all flanges/unions, as I didn't want to take any chances with a potential restriction, etc. But I'm 'only' running 342bhp at the moment though.
11 March 2011, 12:29 PM
#3
This is depend on more factors,if you have good 2.5" will be OK/or should be for 400bhp,but if you have not effective 3" exhaust you have same problem again...
I'm running 2.5" and seems will be OK for 400/450bhp,my mapper said is OK/or should be OK for my needs(400bhp-450bhp)
Jura
I'm running 2.5" and seems will be OK for 400/450bhp,my mapper said is OK/or should be OK for my needs(400bhp-450bhp)
Jura
11 March 2011, 04:12 PM
#5
A lot of conjecture on this.
Some people advocate that a 2.5" is good for upto 400 or even 450bhp! Beyond this, it's worthwhile going to 3" to do away with any potential restriction.
I personally have a full genuine 3" system i.e. inc. all flanges/unions, as I didn't want to take any chances with a potential restriction, etc. But I'm 'only' running 342bhp at the moment though.
Some people advocate that a 2.5" is good for upto 400 or even 450bhp! Beyond this, it's worthwhile going to 3" to do away with any potential restriction.
I personally have a full genuine 3" system i.e. inc. all flanges/unions, as I didn't want to take any chances with a potential restriction, etc. But I'm 'only' running 342bhp at the moment though.
11 March 2011, 04:31 PM
#6
lol at first I thought "Eh?"... Then I saw the poster! 
Funny you should say that though, as the car is due it's BIG 45k cambelt service soon, and I'll do the plugs and everything else on the SSS as a matter of course.
It'll be IRO 800 big ones though, I reckon.
Funny you should say that though, as the car is due it's BIG 45k cambelt service soon, and I'll do the plugs and everything else on the SSS as a matter of course.
It'll be IRO 800 big ones though, I reckon.
Trending Topics
11 March 2011, 06:28 PM
#8
12 March 2011, 08:44 AM
#9
Scooby Regular
Thread Starter
iTrader: (9)
Join Date: Nov 2010
Location: Hertfordshire
Posts: 485
Likes: 0
Received 0 Likes
on
0 Posts
Cheers guys. As I said before I have an unknown decat, but Hayward and scott system from cat back. I was told these are pretty good??? If I was to go for a full 3" system any recommendations? Thank you 
Thread
Thread Starter
Forum
Replies
Last Post
fatboy_coach
General Technical
15
18 June 2016 03:48 PM