Tru Power Engine Kit. 4-Cylinder Gas, 113 CID, 3" Standard Bore, 3-1/8" Overbore Supplied. Stepped-Head Standard Compression Piston, Cylinder Sleeve 3-5/16" O.D. at Seal, 4-25/32" Valve Length. Basic Engine Kit, less bearings. Contains sleeves & sleeve seals, pistons & rings, pins & retainers, pin bushings, complete gasket set, crankshaft seals. For A Series, AV Series, B Series, BN Series, Super A Series (prior to S/N 255417), Super AV Series (prior to S/N 255417), C Series.