2.5 inch or 3 ????

[91TSi]

Just wondering if it will be safe to run 3 inch all the way back including downpipe. I will be on stock turbo at 15psi but I plan on getting a ball bearing in the future. Is it ok like that or should I go with 2.5??
Thanks in advance,




Robert

 

[L2RTSiAWD]

3-inch all the way back.

 

[Otis]

The only problem you may run into is boost creep. Espically on a smaller turbo. Port the #@%#@%#@%#@% out of your O2 housing and hope for the best, as that does not always cure boost creep. You should be okay though. Just make sure you have an aftermarket boost gauge and watch it at WOT. It can creep up high enough to hurt your car if you are not careful.

 

[98TsiAWD]

If you get the o2 eliminator 3" turbo back from RnR Racing then you wont have to worry about porting your o2 housing, because it is gone.

 

[RippinGSX]

If you get 2.5" or 3" and stick with an O2 housing port it and the manifold and the turbine housing. The biggest thing your gonna want to port is the wastegate hole as big as possible without loosing the seal when the flapper door is closed. This will pretty much get rid of creep. The O2 housing port job will help but if you don't do the wastegate hole it will still creep like a mother

 

[Otis]

yeah no one believes me here that porting the 02 will not eliminate the possibility of boostcreep. The real best way is to port the hole for a bigger wasategate flapper, but that is a pretty extensive job. Boost creep sucks. It is just one of those things though Takes $$$ to beat it...
mmmm...external.....

 

[RippinGSX]

If they don't believe it they need to do more research Porting the wastegate hole is actually the least time consuming thing out of any o9f the portwork that needs to be done. I have about 15+ hours into my portwork.

 

[diamondude]

Ok--What does Boost creep mean?-sorry to be ignorant, but if I don't ask I won't know

 

[Tallen]

haha, i met a guy at the track last nite who had boost creep. he actually used it to his advantage. "as i go further down the track my car automatically upps the boost for me. who needs a computer?"
...what a trip

 

[RippinGSX]

Boost creep is when your boost level rises above your preset level and keeps creeping up and up. This is mainly caused by the inability to adequately vent the extra exhaust through a small wastegate.