Anyone know if I swapped out the gsr pistons for USDM type r pistons, which will raise the compression from 10:1 to around 10:8(gsr higher compression head) and along with a mild port and polish with skunk2 stage 1 cams, would pass CA emission? If not, is there anyway to pass the emission? like lean out the fuel with fuel controller or putting on a thicker head gasket etc.. Also, what would be an ideal compression ratio for street daily driven for all motor and wont reguire any octane boosting??? Does anyone have prices on a mildly built gsr head? mildly as in a bit more agressive port and polish then a type r head. thanks