well it depends, if you are going NA or turbo because if you go NA you're gonna wants something w/ shorter gears like the B16 or B18c5 but if you are going turbo get something w/ longer gears like the B18c1 or the B18a/b, also if you get the ITR tranny keep in mind that you're gonna be severly limiting your top speed so like you're gonna be crusing on the highway in 5th at like 4000 or 4500