Well i have been doing alot of researching for my Z6 build and i am planning on running eagles/vitaras, just like almost everyone, lol. But i have been noticing that those setups have been ranging in power so much, like say a z6 with eagles/vitara's, cam, t3/t4 .57 on 15psi will range from say 200hp to over 300. I know that there is alot more involved in the setups but what would be the key factors to making these different amounts of power? fuel? Turbo?