I have a single turbo gtr, and have tuned quite a few. IMO i think they are overrated, for less $$$, you can keep twins, get better response, and make far more power than the standard engine can handle. Dirtgarage is making close to 500awkw, with lowmount turbos. They stock rb26 internals are really only good for a long term 320rwkw, any more and it will go, just give it time.