Chevy ZZ572/620 Base Engine

A 620 horsepower big block base engine is the perfect base for a lot of different high performance engines. Take it drag racing or rumble down the local cruise strip. Either way, you'll turn heads with this strong runner. ZZ572/620 long blocks include all the features of the Deluxe engine except the water pump, carburetor, intake manifold, distributor and spark plug wires. The 620 features rectangular port aluminum cylinder heads with 9.6:1 compression ratios allowing it to run on pump-gas. A smooth running hydraulic roller cam with 0.632" lift pushes the stainless steel valves. Chromemoly retainers, roller rocker arms and dual valve springs help make the valvetrain nearly indestructible.

NOTE: Intended for pre-1977 street vehicles and all off-road vehicles. Not intended for marine use.

Possible Applications

  • Massive hot rod powerplant
  • Wake up the neighbors
  • Top performing BBC

*Applications have not been validated. They are merely suggestions of how you might enjoy your GM Performance Parts crate engine. Some applications may affect engine warranty. See specific warranty information. Some applications may not be emission legal; check state and local ordinances.

Part Number: 12498792
Engine type: Chevy big-block V-8
Displacement (cu in): 572
Bore x stroke (in): 4.560 x 4.375
Block (P/N 25534368): Cast iron with 4-bolt main caps
Crankshaft (P/N 88961554): Forged steel
Connecting rods (P/N 88962926): Forged steel, shot peened
Pistons (P/N 88962925): Forged aluminum
Camshaft type (P/N 88961557): Hydraulic roller
Camshaft lift (in): .632 intake / .632 exhaust
Camshaft duration (@.050 in): 254'c1 intake / 264'c1 exhaust
Cylinder heads (P/N 12499255): Aluminum rectangular port, 118 cc chambers
Valve size (in): 2.25 intake / 1.88 exhaust; stainless steel
Compression ratio: 9.6:1
Rocker arms (P/N 12361323): Aluminum roller style
Rocker arm ratio: 1.7:1
Distributor (P/N 88961867): HEI
Carburetor (P/N 88961560): 850 cfm
Water pump (P/N 14058915): Aluminum, short-style
Spark plugs & wires: Included
Flexplate (P/N 12561217): 14"
Recommended fuel: 92 octane
Ignition timing: 36'c1 total @ 5000 rpm
Maximum rpm: 6000

ezz572 - 620 Base Engine Image

Part #:12498792

zz572 - 620 dyno image

Installation Notes

  • Clutch linkage boss is cast and machined in block, but must be drilled and tapped. When using cast iron exhaust manifolds, lower head bolts may need to be replaced with bolts with shorter heads, for clearance.
  • Requires additional parts (not included).
  • Gen VI tall-deck block has machined mechanical fuel pump boss
  • Comes with a 14" automatic transmission flexplate. Requires internally balanced flywheel for manual transmission applications.
  • Intended for pre-1977 street vehicles or all off-road vehicles.
  • Not intended for marine applications.
  • You do have a strong transmission and rear axle, don’t you?