just done one with 8.1 comp ratio je pistons balanced crank and rods f1 conrod bolts big port head bd16 bd14 gt 30 55lb siemens ecc4 inlet and that made 449 at 1.6 bar and 502 at 2bar with 442lb/ft all on engine dyno so rekon youl be pretty close to that. danny@abcmotorsport