I would just buy a complete d16 engine. They're cheap and every little bit of displacement helps. Not to mention the fact that d15 rods are like toothpicks.

Secondly, forget the fuel rail and cam gear. You don't need them.


However, if you decide to do a head swap I've got a friend with 2 d16y8 heads lying around. Full internals, intake manifold, the works.