Editing Chevrolet big-block engine (section)

===ZZ632===
In 2021, [[Chevrolet Performance]] presented the largest and most powerful crate engine in the brand's history—the ZZ632/1000 crate engine. It is a [[naturally-aspirated]], {{cvt|632|CID|L|1}} V8, producing {{cvt|1004|hp|0|lk=on}} and {{cvt|876|lb.ft|0|lk=on}} of torque.<ref>{{cite web|url=https://www.motortrend.com/news/chevrolet-performance-1000-hp-zz632-crate-engine/|title=Biggest Crate Engine Ever! Chevy Performance Launches 1,000 HP ZZ632 Big-Block|date=20 October 2021}}</ref> The motor itself weighs {{cvt|680|lb}}.<ref>{{cite web |url=https://www.karlkustoms.com/product/chevrolet-performance-zz632-1000-crate-engine/ |title=Chevrolet Performance ZZ632/1000 Crate Engine |publisher=KarlKustoms.com |date= |access-date=2022-04-11}}</ref>

According to Russ O'Blenes, the GM director of the Performance and Racing Propulsion Team, the ZZ632 is the "biggest, baddest crate engine we've ever built. [It] 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."<ref>{{cite web|url=https://media.chevrolet.com/media/us/en/chevrolet/home.detail.html/content/Pages/news/us/en/2021/oct/1020-crate.html|title = Chevrolet Performance Unveils Its Largest, Most Powerful Crate Engine Ever|date = 20 October 2021}}</ref>

The big-block V8 reaches peak power at 6,600&nbsp;rpm, and revs to a recommended maximum of 7,000&nbsp;rpm. Fuel is delivered through eight-port injectors, with the engine breathing through CNC-machined high-flow aluminum cylinder heads featuring symmetrical ports. While big-blocks have usually been designed with variations in port shape from cylinder to cylinder, all eight intake ports of the ZZ632 have the same volume, length, and layout. Furthermore, all of the ZZ632's exhaust ports are identical. This arrangement guarantees all individual cylinders produce similar power.<ref>{{cite web|url=https://www.motorauthority.com/news/1133914_chevy-unveils-biggest-most-powerful-crate-engine-to-date|title = Chevy unveils biggest, most powerful crate engine to date}}</ref>

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 V-8, with the Gen III [[General Motors LS-based small-block engine|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 huge 632 cubic-inch displacement. The bore grows by {{cvt|0.040|in|1}}, compared to the 572-cubic-inch V8s, with most of the displacement gain coming from a stroke that is {{cvt|0.375|in|1}} 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 assure strength and durability. During development, a single engine endured more than 200 simulated drag strip passes on a dynamometer.

The ZZ632/1000 crate engine was slated to be on display at the November 2021 [[SEMA (association)|SEMA Show]] in Las Vegas. Chevrolet Performance dealers were to begin deliveries in early 2022.<ref>{{cite web|url=https://www.roadandtrack.com/news/a37990530/chevy-1004-hp-crate-motor-zz632-1000/|title=Chevy Has a New 10-Liter Crate Motor That Makes 1004 HP|date=20 October 2021}}</ref>