another crazy question for you seasoned pros out there.the engine blocks out of the z32 and z21 are the same block right? if so does that mean the heads are interchangeable?

is it really possible to swap heads off a z32 engine onto a z31?
would you see a decent gain in power becuase of the 4 vavle design?

any thought /input much appreciated.

 

Blocks are not same.No external parts can be interchanged.