Tru Power Engine Kit. 6-Cylinder Gas, 221 CID. 3-9/16 inch Standard Bore. Stepped-Head Piston, 1-21/32 inch Intake Valve Head, 3-3/4 inch Thrust Bearing Flange. Engine Overhaul Kit, less bearings. Contains sleeves & sleeve seals, pistons & rings, pins & retainers, pin bushings, complete gasket set, crankshaft seals, intake & exhaust valves, springs, guides, valve keys. For 460 Series.