Chevrolet Performance Part 19432105 ZZ6 350 Turn-Key Crate Engine

Chevrolet Performance builds this ZZ6 350 around aluminum Fast Burn cylinder heads and LS-style beehive valve springs, a combination the maker says makes it one of the most powerful 350-based engines in the more than 25-year run of its "ZZ" crate engine lineup. Output comes in at 405 horsepower, with 406 lb-ft of torque on tap.

What the beehive springs change

The egg-shaped beehive design trades a heavier dual-spring setup for a lighter coil that needs less seat pressure to keep the valve under control at high rpm. Paired with the Fast Burn combustion chamber shape, the result is a small-block that keeps pulling as revs climb, rather than one tuned mainly for off-idle grunt.

Before you order

This unit is listed as a turn-key build, so confirm with us exactly which accessories and induction hardware ship installed before you plan the rest of your swap budget, since turn-key packages can vary by supplier. The small-block architecture underneath means standard Chevy motor mounts, bellhousing patterns, and accessory brackets are a reasonable starting point, but check them against your own chassis and transmission before ordering.

Q: Is this engine more powerful than the small-blocks Chevrolet has sold in production cars? Chevrolet Performance says so, calling this one of the strongest 350-based engines in its 25-plus years of ZZ crate engine production.

Q: What makes the valve springs different? They use an LS-style beehive design instead of a traditional dual spring, built to support higher rpm operation without added spring pressure.