Originally Posted by sc00ter
I'm late to the party but have the setup you seem to be looking for...
- VF48 (bolts up just the same as a VF39 & VF43)
- STI TMIC & STI splitter (both from an '07 STI)
- SPT intake (not a necessity)
- Perrin turbo inlet (*read note below)
- Walbro 255 fuel pump **Not needed
- Stock injectors (*read note below)
- COBB 3" catted TBE
When I was looking to do this upgrade I looked here then contacted 2 local reputable tuners. The above setup was the general consensus to make the upgrade work properly.
If you have the stock intake on the car, keep it. My tuner liked the SPT intake but said he could have achieved the same numbers with the stock intake as well. I already had the SPT intake installed so I just stuck with it.
* When installing the VF48 we discovered that my stock turbo inlet had a couple of small tears near where it connects to the turbo. So I installed a new Perrin one in its place. I've read that the stock inlet has a tendency to tear/rip like mine did on the '06-'07 models. Because of this I recommend planning ahead and just replacing/upgrading the inlet when you upgrade the turbo.
* The stock injectors should be plenty adequate for the VF39/VF43/VF48 with 91-94 octane fuel. My tuner recommended that I stick with the stock injectors since I wasn't planning on going e85. with the tune, at 19psi, I believe my maximum duty cycle on the injectors is around 85% so there is plenty of headroom.
(Note that if you plan on going with e85 you will NEED TO upgrade the injectors.)
Fuel pump is not needed unless you upgrade injectors, stock fuel pump flows more than enough for stock injectors.