Currently am running B18C1 engine with a reworked head and ITR cams. The head has been milled .012". My question is if there would be an issue with piston to head clearance if I swapped to a type r block. The head with its mild internals seem to be pretty awesome as it is, but would like to put a fresh block under it and bumb up the compression as well. I figure the compression to only be slightly over stock at the moment since material was removed form the combustion chamber.

I had always felt that the excellent quench area and small combustion chambers of the gsr head would make an outstanding setup if the ports were improved (for a mild build). This is what we would have here, but I don't want to wind it up and have internal engine components contacting each other. Does anyone know the critical clearance?