silverbullet

Quick question:

If you have a Vitesse Stage 2 or 3, how important is it to have a 3'' downpipe? Does anyone know how much hp could you lose if you kept the stock one?

Thanks!

sweanders

I thought a lot about the change and decided to stay with the stock downpipe. When looking at the available 3" DP's thay are obviously larger in inner diameter but don't have as smooth bends as the stock downpipe.

I don't know if it is correct though, if I feel a lack of power with the S3 turbo I'll go for a bigger dp, or maybe just crank the boost up a psi or so..

TRP951

If I recall correctly ST had the stock downpipe on his car for his 407rwhp dyno run

special tool

It made 472 at the wheels with stock downpipe, headers and x-over.

Dr. Dynamics

Silverbullet,

As a suggestion, it is not required to accomplish high numbers, but it will let you accomplish them safer.
What your planning will improve the volumetric efficiency and will make the turbo work in a more efficient area of the map. This translates into less combustion temperatures and eventually less boost required for a certain hp number which also translates into less head gasket changes in our cars.

If the budget is not an issue...go for it, that's what I'm planning to do...

eclou

The main issue I see with the 3" downpipe is getting the damn thing in there requires an R&R of the turbo. I can barely get the stock DP in and out with the turbo in place. For me, it would be one of those "while I'm in there" items.

ibkevin

Good question Josh. Since my second Turbo Performance 27/6 is experiencing blade tip curl at 100 miles and will be pulled, I considered the 3" downpipe also. As long as I run a cat, prolly not worth the $$.