if you have the money rb26 is the way to go. the 2.0 and 2.5 can be made powerful but are not as reliable as the 2.6. If you want a peppy ride the 2.0 is good. but the sr20 is a lot lighter and about the same power. the 2.5 is also good and can make some serios power with bolt ons. ultimatley its up to ... all the motors need some fabrications to fit but are well worth the effort.