Genuine GM 12568774 Engine with Iron Head and Roller Cam

This engine is not designed, nor intended to be used in any marine applications. Designed for pre-1976 street vehicles or any off-road vehicle. Engines installed in vehicles registered and normally operated outside of the United States carry no warranty. Clutch linkage bosses are drilled and tapped, plus includes a provision for a mechanical fuel pump. The 454 HO offers tremendous value in a big block crate engine. Based on the Gen VI 4-bolt mains with 1-piece rear main seal blocks with approximately 8.75:1 compression, 425 horsepower at 5,250 rpm and 500 feet/pounds of torque at 3,250 rpm. The "HO" stands for high output, which means you get forged steel externally balanced crankshafts, forged steel LS6/LS7 "Dimple" rods, shot peened and magna fluxed with 7/16 inch rod bolts. Forged aluminum pistons, hydraulic roller camshafts with .510 inch intake lift, .540 inch exhaust lift and duration at .050 inch for intake is 211 and 230 for exhaust, lobe centerline is 112 degrees. Cast iron cylinder heads with rectangular port 118 cubic capacity combustion chambers, 325 cubic capacity intake runner volume with 2.19 inch intake valves and 1.88 inch exhaust. These heads are configured for 3/8 inch thread 7/16 inch shank rocker arm studs. Stamped steel self-aligning 1.7:1 ratio rocker arms come installed along with AC Delco spark plugs. Also included with these crate engines; oil pans, black powder coated aluminum valve covers, black powder coated aluminum timing covers, long style cast iron "V" belt rotation water pumps, 8 inch harmonic balancers, and 14 inch automatic flex plates.