A legendary foundation with Turn-Key ease Chevrolet Performance’s SP350/385 Turn-Key uses new-casting Fast Burn cylinder heads equipped with LS-style beehive valve springs for greater high-rpm performance. The lightweight aluminum cylinder head casting is based on the proven Fast Burn design, with large intake runners and 2.00/1.55-inch valves. New beehive-style valve springs enable greater high-rpm performance and durability. They allow the SP350/385 to rev higher to make the most of every cubic inch of air drawn through it. The SP350/385 is built with a brand-new block with four-bolt mains, along with a forged-steel crankshaft, an aggressive hydraulic roller camshaft, and durable, high-silicon pistons. Unique valve covers distinguish this new crate engine at a glance, too—along with Chevy bowtie insignias in the ends of the cylinder heads that let everyone know you have the latest Chevrolet Performance hardware under the hood. The Turn-Key engine package includes the distributor, carburetor, and balancer installed. The starter, fuel pump, air conditioning pump, alternator, front-end accessory drive kit, and more are also included.