Also having more backpressure on the turbo is bad for the exhuast part of the turbine fan. The faster it gets out the easier it can spool/faster---ABC easy as 123

 

Hold your thumb over the end of the garden hose and create mucho velocity, but also more back pressure. Now, do the same on your tail pipe with a reducer (or your thumb). Does that make performance sense just to get exhaust velocity? I don't think so. If you were to remove your test pipe completely wouldn't you theorictcally be running the turbo at max due to zero restriction on the back side? So bigger is better on the exit pipe but at some point (3 inches?) you have past the point of economic return from buying all the stainless steel.

 

Ya I am running the GT28RS with around 20psi -I think, whatever ATPsoftware uses; future setup- and I was thinking3" due to the larger turbo... I had 2.5 on my last k04 setup but I thought bigger would be better. Thanks for all the help guys.

 

Stop thinking. This thread is making me angry and I never get angry over the internet.

 

thats pretty much what everyone is saying. im gunna run 3" pipe when i put in my BT.

 

Ok well I'm going three inch and plan on taking many pics to post on the job. Thanks for the help and wow guys it's just exhaust... [sm=happybounce.gif]

 

an exhast is very impornt. bigger is better up tell of point of diminishing returns like cincy said. get a 3" with the least amount of bends as possible. this will give the most power and best spool