When introduced at the Detroit Auto Show back in January, the 2009 Chevrolet Corvette ZR1’s power was estimated at more than 100hp for each liter of its 6.2L of supercharged V8. GM has lived up to that promise and delivered an official SAE certified power rating of 638hp (476kW) and 819Nm (604lb-ft) of torque.

This puts the LS9’s output at nearly 103hp per liter, or just about 1.7 horses for each of the engine’s 376 cubic inches. It also makes the new powertrain the most powerful engine ever released by GM in a production car and ensures the Corvette ZR1 is able to reach speeds in excess of 200mph.

The supercharged V8 is hand-built by specially trained technicians at GM’s Performance Build Center in Wixom, Michigan. The site is a unique, small-volume engine production facility that also builds the Corvette Z06’s LS7 engine and other high-performance GM production engines.

Key to the engine’s performance is a forged steel crankshaft with a nine-bolt flange, titanium connecting rods and forged aluminum pistons, rotocast cylinder heads with titanium intake valves and sodium-filled exhaust valves, a dry-sump oiling system with integrated oil coolers and, of course, the positive-displacement Roots-type supercharger.

The design of the supercharger promotes quieter and more efficient performance, while the large, 2.3L displacement ensures adequate air volume at high rpm. Maximum boost pressure is 10.5psi (0.72bar).

The Corvette ZR1 goes on sale in the middle of the year and is tipped to be the most fuel-efficient 600hp-plus vehicle on the market.

2009 Chevrolet Corvette ZR1