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Chevrolet Performance Unveils ZZ632/1000 Crate Engine

Chevrolet Performance today introduced the ZZ632/1000 crate engine — the largest and most powerful crate engine in the brand’s history. The naturally aspirated 632-cubic-inch V8 produces 1,004 horsepower and 876 lb-ft of torque.

“This is the biggest, baddest crate engine we’ve ever built,” said Russ O’Blenes, GM director of the Performance and Racing Propulsion Team. “The ZZ632 sits at the top of our unparalleled crate engine lineup as the king of performance. It delivers incredible power, and it does it on pump gas.”

The Big Block V8 reaches peak power at 6,600 rpm and revs to a recommended maximum of 7,000 rpm. Fuel is delivered by eight-port injectors with the engine breathing through CNC-machined high-flow aluminum cylinder heads featuring symmetrical ports. While Big Blocks have traditionally been designed with variations in port shape from cylinder to cylinder, all eight intake ports of the ZZ632 have the same length, volume, and layout. Similarly, all of the ZZ632’s exhaust ports are identical. This symmetry ensures individual cylinders all produce similar power.

These RS-X Symmetrical Port cylinder heads are named for powertrain engineer Ron Sperry, who designed them as one of his final accomplishments in more than 50 years working on General Motors performance and racing engines. Sperry also introduced symmetrical ports to Chevy’s iconic Small Block V8 with the Gen III LS1 engine that debuted in the 1997 Chevrolet Corvette.

The ZZ632’s iron block shares a mold with Chevrolet Performance’s ZZ572 crate engines, but the castings are machined to accommodate the massive 632-cubic-inch displacement. The bore grows by 0.040 inch compared to the 572-cubic-inch V8s, with most of the displacement gain coming from a stroke that’s 0.375 inch longer. To provide clearance for that long-stroke, engineers modified both the block and the connecting rods. Four-bolt main caps and a forged rotating assembly ensure strength and durability. During development, a single-engine endured more than 200 simulated drag strip passes on a dynamometer.

The ZZ632/1000 crate engine will be on display at the 2021 SEMA Show in Las Vegas, Nov. 2–5. Chevrolet Performance dealers will begin deliveries in early 2022.

Chevrolet Performance ZZ632/1000 
Displacement632 cu in (10,348 cc)
Bore x Stroke4.60 x 4.75 in
Compression Ratio12.0:1
Power1,004 hp @ 6600 rpm
Torque876 lb-ft @ 5600 rpm
Maximum Recommended Engine Speed7,000 rpm
BlockTall Deck 632 Bowtie Sportsman, cast iron, four-bolt main caps
Cylinder HeadsRS-X Symmetrical Port, CNC-machined aluminum
CrankshaftForged steel
Connecting RodsForged steel
PistonsForged aluminum
FuelElectronic port injection

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