Yo I got a 99 Civic Si and im swapping a JDM Civic SiR Cylinder Head that has: 3 angle valve job , swirl marked valves , shaved valve guides both intake and exhaust ports , intake ports were opened up 3mm all the way around, intake ports are sand blasted , knife edged intake and exhaust ports, fully polished combustion chambers , cylinder head is CFM'c and CC'ed to make sure all combustion chambers are even and exact. I am wondering a few things about this swap. The cylinder head is also milled. Can replacing the head raise compression, and/or can a head gasket raise compression? I am also assuming raising the compression of the pistons and/or boring them out can provide an enormous power increase especially with this head.. is this true?