4.07" bore--4.250" stroke--268* at .050 x .560" lift Racer Brown solid flat tappet cam--11.75 to 1 CR--nicely ported 587 production cyl heads-- Victor 340 intake--1000cfm carb--1 3/4" hooker headers. Should make 1.6 HP per C.I. Actually ended up 442 C.I. because piston manufacturer made pistons for 4.07" bore instead of 4.06" bore, as I ordered a similar set for a 340 based engine at .030" over the same time I ordered pistons for this engine. 360 block for this project plenty thick enough to go .100 O.S.