Corvette Gets 7-liter Engine

by: John Hartley


You might think that 6 liters was enough to make the Corvette two-seater fast enough, but not for the competition department lurking inside GM. They wanted to be able to compete head-to-head with the European supercars in the international endurance races for sports cars.

To do so, they took a leaf out of Ford's book. In the 1960s, when Ford found it could not compete with the smaller Ferraris at Le Mans with the 4.2 (ex-Indy) or 4.7 liter engines, they brought out their 7-liter mill. And it was so much bigger than the competition that they won. So the guys behind the Corvette decided to produce a 7-liter version of America's favorite and most famous sports car.

By the way, the 7 liter Corvette more than competes with the Dodge Viper SRT-10, which could give the standard Corvette a bit of a run for its money. Of course, this is not just any old engine. This is a very special version of its GEN IV 7.0 liter V-8.

This 2006 Corvette is challenging for muscle car of the year with no less than 500 bhp on tap at 6,200 rpm. Maximum torque from this mammoth engine is 475 lb ft at 4,800 rpm. This is bound to be a stunner with a top speed of about 185 mph and 0-60 in under 4.0 seconds. GM expects the quarter-mile be under 12 seconds.

To give durability, the engine has been beefed up in a number of ways. First, the connecting rods and inlet valves are now made of titanium – these weigh about half as much as steel ones and are used in quite a number of high-performance engines. Because of the low weight, the titanium parts put less load on other critical parts of the engine - the crankshaft, bearings and in this case the valve gear as well. The titanium valves also allow the engine to rev faster safely.

In fact, titanium used to be an aerospace-only material because it was so expensive, but it is now bein gused more in exotic cars and the heads of golf clubs, helping the lesser pros feel not so outclassed by Tiger Woods as they might with ordinary drivers.

You will see that the Corvette 7 liter is intended for the race track by the fact that the engine has a dry sump lube system. A dry sump system prevents the oil in the oil pan from slopping away from the pick-up on fast cornering – the sort you can do only on a track – and thus damaging the main bearings.

Instead of staying in the oil pan, the oil is pumped out to a tank, and then pressure fed from there directly to the engine bearings and other critical areas. Definitely a system for top supercars.

The underpinnings of the car have also been beefed up with a new aluminum perimeter frame which reduces weight. Further weight reduction comes with a new magnesium engine sub-frame. To ensure the car is stiff enough, it will be available only as a hardtop. The front fenders and wheelarches are now carbon fiber composite panels, which also reduce weight.

But there’s more…

To get all that power onto the road, and to get it to stop, bigger wheels, tires and brakes have been fitted. The front brake discs are now 13.9 inch diameter, and 19 x 12 inch wide rims are used at the back; front wheels are 18 x 9.5 inches. Such massive rear tires for a car with 50:50 weight distribution suggest that the car will have a tendency to oversteer – smoky drifts could be the order of the day!

All-in-all, this is a really special car, developed to compete with the best.


About The Author

John Hartley is editor of http://www.fast-autos.com, an online magazine devoted to fast cars and supercars. He has written from many of the world's top auto magazines, and has written many books about cars and the auto industry.