The design of our BMW S65 stroker longblock follows the successful formula of our S85 stroker, with just two fewer cylinders and slightly more agressive camshafts. It employs the Arrow billet 82.7mm crankshaft available exclusively through VAC Motorsports, Carrillo or Arrow rods, and our proprietary 2618 alloy pistons made for us by JE in 94mm bore and with ringlands that accommodate the race-proven BMW S62 ringset. Combined with our ported heads, uprated valvetrain, and Schrick 292 duration camshafts, the result is 4.6l of reliable high revving naturally aspirated power in the mid to high 400whp range--exactly as the S65 should have come from BMW in the first instance. Other combinations of stroke and bore are available, but this is the combination we strongly recommend. Price below does not include the $4500 core charge if applicable. See the Core Charge Policy for details.