A 3" over a 2.5" should begin to show gains when over around 350bhp - although it depends on the design of both! If you don't mind the additional noise & cost, it's probably worth your while at 400bhp+.
IMHO

 

I thought most aftermarket exhausts were 3", incl Scoobysport. I thought only the standard exhaust was 2.5"?

 

Nom: Thanks for the info, does the 3" make a lot more noice than an open scoobysport system? The 3" system will probably be Invidia.

Slowboy: From what I've heard the SS is 2.5". I wish it was 3".

Derk

 

3" sounds wicked on the boxer motor, you aint heard a scoob till you hear one with a 3"

 

Pitzi : Ok We'll keep that in mind :-).

Derk

 

3" sounds the dogs

H&S sell the 3" for the same price as the 2.5" ..

 

Hi There,

Can anyone tell me what benefits it has to fit a 3" exhaust system, instead of the Scoobysport exhaust that is now fitted. It concerns a 2.5 Liter engine. (mildly tuned to 405 bhp)

Does it respond a lot better, or what else does it give me ?

Derk

Oops, I just now realise that this topic should have been posted in Drivetrain. Sorry

[Edited by Derk GTT - 9/12/2003 5:04:43 PM]