GM Details New Corvette Engine

Standard versions of the next-generation Chevrolet Corvette sports car will be powered by an all-new, 6.2-liter V-8 that makes 450 hp and 450 lb-ft of torque.

General Motors Co. released details about the car's new LT1 engine today. Among its technical features are direct injection, an advanced continuously variable valve timing system, an 11.5:1 compression ratio and the Vette's first use of cylinder deactivation.

The generation-five small-block engine will propel the new Vette from zero to 60 mph in less than four seconds but also help the car achieve an Environmental Protection Agency fuel economy rating of 26 mpg on the highway, according to the company.

GM says its engineers devoted more than 10 million hours of computational analysis 60% of it related to the combustion system to develop the powerplant. The engine's direct-injection fuel system reduces cold-start hydrocarbon emissions by about 25%.

The new engine has an all-aluminum block and structural oil pan. A standard variable-displacement oil pump sprays extra oil onto the cylinders during startup and at high engine speeds but not during moderate driving when the additional lubrication isn't necessary. A dry-sump oiling system is optional.

A high-pressure (up to 150 bar) fuel pump, driven directly by a special lobe on the rear of the engine's single camshaft, is fed by a conventional fuel pump within the fuel tank.

Domed rocker covers incorporate a built-in positive crankcase ventilation system, spark plug ignition coils and baffles that separate oil from crankcase gases three times as effectively as in previous engines. The intake manifold encloses individual runners that feed a plenum box, a configuration intended to boost air flow efficiency.

The combustion chambers in the LT1 are smaller than those in the current Vette's standard 436-hp LS3 V-8, and the position of the intake and exhaust ports are reversed. Iridium-tipped sparkplugs protrude slightly farther into the combustion chamber to improve fuel burn.

GM plans to publicly unveil the new Corvette in January at the Detroit auto show.