Published on October 5th, 2015 | by Subhash Nair0
Chevrolet Performance Details New ZZ6 Crate Engines
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. A pair of high-flow, Fast Burn-style aluminium 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 aluminium pistons housed in a four-bolt-main cast iron block.
A pair of all-new, aluminium 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 aluminium 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.