i take the "under dog" b16 because there is more of a rpm band. they have things to help the extra rpm's too. youd be lucky to get a b18b to rev to 8500 but a b16 would be no prob. so i say that the b16 will be better all motor. it has better flow ratings, the integra type r's head is basically the same as the b16, as far as the mold of the empty head. the b16 block is smaller but at the same time it has better oil supply than does the b18b. these are just a few reasons that i am thinking that a b16 is better for all motor in the long run.