It's a good idea for a specific kind of power curve.... if you know anything about how stroke geometry makes an engine behave, you can tailor your engine build to suit the types of power curves you want to make. A B16 crank in a B18 block is basically the same as the B16B from the factory, and is capable of some very high revs. It's good for high revving power, but not much torque down low... which is perfect for a light car with short gearing on a road course.