Old part# 12498793
The ZZ572/620 is built around an all-new Gen VI tall deck race block, filled with a forged, 4340 steel, 4.375” stroke crankshaft, shot-peened rods, and forged aluminum pistons.
620 HP 650 Torque The ZZ572/620 is built around an all-new Gen VI tall deck race block, filled with a forged, 4340 steel, 4.375” stroke crankshaft, shot-peened rods, and forged aluminum pistons. The newly redesigned rectangular port aluminum cylinder heads result in a pump gas friendly 9.6:1 compression ratio. Also included is a .632” lift, hydraulic roller camshaft, roller rockers, dual valve springs, single-plane intake manifold, and an 850cfm Demon carburetor. A GM HEI ignition feeds the ZZ572/620 all the electricity it needs to yield 620hp and 650 ft. lbs. of torque! ZZ572 / 620 Technical Information ·HP: 620 @ 5500 RPM ·Torque: 650 Ft. Lbs. @ 4500 RPM ·Compression Ratio: 9.6:1 ·Bore: 4.560” ·Stroke: 4.375” ·Block: Bowtie Tall Deck with One-piece rear seal ·Crankshaft: Forged 4340 Steel ·Connecting Rods: Forged 4340 Steel, H-Beam style, Shot peened ·Pistons: Forged aluminum with full floating wrist pin ·Piston Rings: Plasma-moly rings ·Camshaft: Hydraulic roller (.632” / .632” lift) (254 / 264 duration @ .050”) ·Lifters: Hydraulic Roller tappet ·Cylinder Heads: Aluminum Rectangular Port with a 118cc combustion chamber ·Intake Valves: 2.25” Stainless Steel ·Exhaust Valves: 1.88” Stainless Steel ·Valve Springs: Dual spring (1.540” diameter) ·Spring Retainers: Hardened chromemoly steel ·Rocker Arms: Aluminum Roller Rockers, 1.7:1 ratio ·Push Rods: High Performance (1-piece) ·Intake Manifold: Aluminum Tall Deck single plane ·Carburetor: 850cfm, mechanical secondary ·Windage Tray: All new Screened and Louvered design ·Damper: High RPM torsional damper ·Distributor: GM HEI ·Ignition Timing: 36 degrees total advance ·Spark Plugs: R42XLS ·Fuel: 92 Octane
Manufacturer: GM
SKU: 19201333