Originally Posted by Sqrl
1) Will you provide us with a description of what you liked and/or didn't like in build 1 and build 2, and the pros and cons of each. Was build 2 the same goal as build 1 *with the goal of good low and mid range TQ, throttle response and quick spool up?
2) Which turbo did the RSD team like best? Is one better for one type of driving/goals and the other better for another? I'm sure I'm not the only person agonizing over which turbo upgrade to go with
3) Is there anything you would have done different or that you learned from either build that you can share with us?
We did the build power wise 3 ways. 1 was stage2, 2 was the Tomei Turbo, and 3 was the ATP turbo.
For stage 2 the best thing is that its very simple and used basic Off the Shelf Parts with Off The shelf Tuning. Best part is that you simply get an AccessPort, exhaust, intake, grab a buddy to help you install the parts and a few hours later you have a very safe and easy way to get the most out of the stock turbo.
For the Tomei Turbo, this was a bit involved as we upgraded all the supporting parts other then the Motor internals. The cool thing about this turbo is it really allowed us to max out the fuel we had around us and the instal was very straight forward. The turbo didnt have much more room to go as it was at its efficency, but for pump gas it was perfect.
The ATP turbo was a bit more involved, do to the physical size it was a bit more work to fit including having to do a 3" inlet. If you notice we didnt gain much more peak power numbers over the Tomei on pump gas, as pump fuel was the limiting factor. However it gave us ALLOT more head room to make power on race gas. The catch 22 on the ATP is the turbo has more to give then what we want to push the stock motor past, and as you can tell we stopped in the 380WHP range even though it has more room to go.
Goal for both ATP and Tomei turbo was to simply maximize the stock motor and pump fuel. I wouldnt say that one turbo is better then the other per say as they are simply different. The ATP uses the new GTX series billet wheel so this would be the new Hotness of turbo technology, however the price point shows this. Where the Tomei is a great turbo with out breaking the bank (or the motor). Overall both turbos work great, but do react different. The ATP is more responsive on building pressure and has a much larger power band, however this is to be expected with brand new technology of Billet wheels and ball bearing center cartage.
As for doing anything different, I dont think we would have. We got to try out several products and put up our research on the products for the Subaru community. Learn about what the car likes and doesnt like, and really explore the capability of the car