Chevrolet Small Block (ZZ) Engine Upgrade

The Ultimate Chevy Small Block V-8 Will Be a Phone Call Away

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Chevrolet Performance announced last week from Detroit that they have plans to introduce a new ZZ6 crate engine that could change the way consumers view the Chevy small block engine. This innovative engine is reportedly being developed using the most modern technologies from circle track racing, drag racing, and even Formula 1 racing.

Dyno Chart ZZ6Using some of the same time tested strategies that made them a mainstay among racers of every genre, combined with a contemporary theory of operation that enhances high RPM capability, Chevrolet plans to offer the most powerful 350-cubic-inch engine ever installed in a production vehicle. “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.”

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The stock version of the all-new ZZ6 is expected to produce 405-horsepower and 405 lb.-ft. of torque. That is more power than any 5.7-liter engine ever offered in a production vehicle and one of the most powerful 5.7-liter small block crate engines ever sold by Chevrolet Performance in the storied 27-year history of the “ZZ” lineup.

Bottom End

Providing a firm foundation for the ZZ6 is a cast iron engine block with four-bolt main bearing galleys. A forged steel crankshaft and quiet, durable high silicon aluminum pistons finish out the bottom end.

Top End

ZZ6 Valve SpringsA set of high-flow, fast burn cylinder heads with huge intake runners increase the flow of cool air to the engine. A set of 2-inch intake and 1.55-inch exhaust valves, with beehive-style valve springs, deliver the air/fuel mixture to the combustion chambers and allow spent exhaust gases to escape expeditiously thereafter. The beehive shaped valve springs allow for the use of a smaller retainer assembly which helps to reduce the reciprocating mass of the valvetrain and improve performance dynamics. The tapered shape of the springs also provides exceptional durability, even under high RPM conditions. A set of all-new aluminum valve covers give the ZZ6 a distinctive premium appearance. An aggressive long-duration (208/221-degrees), high-lift (.474/.510) hydraulic roller camshaft opens and closes the valves appropriately to allow this beast to breathe deeply and belch thunder. The cam is designed to provide outstanding high RPM airflow capabilities while yielding optimum low speed driving maneuverability.


Two variations of the ZZ6 crate motor are expected to be made available through local GM dealership parts departments. The first is the base version (P/N 19351532). It will include the aforementioned equipment plus a single plane aluminum intake manifold, distributor, water pump, harmonic damper, and flex plate. The second version is the turn-key setup (P/N 19351533). It adds a carburetor (with an air cleaner housing that matches the valve covers), a starter, distributor, and alternator. Other accessories are also available upon request (no doubt for a nominal fee).

Chevrolet will announce a scheduled availability for both the base and turn key ZZ6 crate engine kits at the SEMA Show (Chevrolet Press Conference) on November 3, 2015.


Photos courtesy of Chevrolet Media.

S.M. Darby

S.M. Darby

I am a freelance author with over 25 years of experience as a professional, ASE certified automotive technician and shop owner, muscle car enthusiast, avid street racer, and classic car restoration specialist.