keep your B17!!!! u want to have a "type r" engine in there? then just put in some internal mods to it... cams, valvetrain, mild head work, ported throttle body, port match the intake manifold to the head... you already have flat top pistons which are cool but if you want to raise compression then i guess you can swap in some b18c/GSR pistons which are slightly domed.

the g2 gsr has the amazing tranny and crank/rod combo... keep it!