id definetley get the b16. It might not be quite as quick, but it will last alot longer. and if you put on i/h/e you'll be jus tas fast.

The d15b turbo will have about the same whp as the b16 but alot more torque. my friend has one w/dsm turbo 8psi boost and he can beat stock gsr's all day. he cant kill um but he would win by around atleast a good 2 cars in 1/4