For the ZZ6, Chevy is working to improve the Small Block's high-rpm performance. To make that happen, the engine has Fast Burn aluminum cylinder heads and an updated valvetrain inspired by the LS family of powerplants. Large intake runners help with the airflow, and the valve springs use a tapered design that allows for less reciprocating mass. The mill also packs a forged steel crankshaft and high-silicon aluminum pistons inside of a cast iron block.
Chevy is offering the engine in two versions depending on what the builder needs. The Base configuration comes with an intake, distributor, water pump, and a few other parts but lacks carburetor and accessories. Conversely, the Turn Key option has everything, including the carb, air cleaner, starter, alternator, and more. More details about their availability will be announced at SEMA.
Revised Fast Burn heads with LS-inspired valvetrain enhance high-rpm performance
DETROIT – Developed with contemporary technologies, including a high-rpm valvetrain, Chevrolet Performance's new ZZ6 crate engine offers builders a modern twist on the classic Chevy Small Block 350.
It uses updated Fast Burn cylinder heads with beehive-style valve springs inspired by the LS engine family – a feature that enhances high-rpm capability, enabling the new high-performance engine to achieve 405 horsepower and 405 lb-ft of torque.
That's more power than any factory produced 350 engine ever installed in a Chevrolet production vehicle and it's one of the most powerful 350 Small Block-based crate engines in the nearly 27-year history of the "ZZ" lineup.
"The new ZZ6 is the ultimate ZZ 350-based crate engine from Chevrolet Performance," said Jim Campbell, GM U.S. vice president of Performance Vehicles and Motorsports. "After more than six decades, our powertrain engineers continue to refine and update the classic Small Block architecture, adapting new technologies to advance the legacy of the industry's most adaptable V-8 engine and giving customers new choices from the company that pioneered the concept of high-performance crate engines."
A pair of high-flow, Fast Burn-style aluminum cylinder heads, with large intake runners and 2.00/1.55-inch valves, enable the ZZ6 to flow big air, while the beehive-style valve springs offer exceptional high-rpm performance and durability. The unique, tapered shape of the valve spring allows for the use of a smaller spring retainer, which reduces the reciprocating mass of the valvetrain resulting in better valve dynamics.
The ZZ6 also uses an aggressive hydraulic roller camshaft, with .474/.510-inch lift and 208/221-degrees duration, that supports the engine's high-rpm airflow capability, while maintaining excellent low-speed drivability. Rounding out the rotating assembly is a forged steel crankshaft and durable, quiet high-silicon aluminum pistons housed in a four-bolt-main cast iron block.
A pair of all-new, aluminum valve covers caps off the new crate engine, giving it a distinctive, premium appearance.
Chevrolet Performance offers the ZZ6 crate engine in Turn Key and Base versions. The Base kit (P/N 19351532) includes a single-plane aluminum intake, distributor, water pump, damper and flexplate, but requires the carburetor and other accessories to be added.
The Turn Key kit (P/N 19351533) includes the carburetor, an air cleaner that matches the unique valve covers, the starter, distributor, alternator and additional accessories such as the air conditioning compressor and front-end accessory drive system.
Availability for the Turn Key and Base ZZ6 crate engine kits will be announced at the SEMA Chevrolet Press Conference on November 3, 2015.
FAST FACT: The first "ZZ" crate engine was introduced in 1989. Dubbed ZZZ, the 350 high-output engine was rated at 350 horsepower.
Driven by more than 100 years of motorsports heritage, Chevrolet Performance fuels the passions of automotive enthusiasts through high-performance vehicles, parts and racing. Performance cars include Camaro SS, SS 1LE, ZL1, Z/28 and the COPO Camaro. Chevrolet Performance parts include crate engines, transmissions, controllers and street-level components. Chevrolet competes in NASCAR, NHRA, IMSA, IndyCar and a variety of circle track racing series. More information can be found at: http://www.chevrolet.com/performance.