C6: 2005-2013Going Out In Style
It's hard to say goodbye to the sixth-generation Corvette. Since its debut nearly eight years ago, we've filled our pages with C6 test drives and shown how a variety of tuners have extracted maximum performance from the car.
Tom Peters, the C6's exterior designer, gave us our first ride in the car in April 2004. He provided us with an overview of his design philosophy for the car, which focused on making it more compact while retaining the Corvette heritage.
Later that year, we attended the 2004 Corvette at Carlisle event, where Carlisle Events' Lance Miller took delivery of his own C6. Shortly after the show, he delivered the car to Callaway Cars for upgrades. We followed these changes in a multi-part series that included modifications to the engine and suspension. This project helped familiarize us with the C6's strengths as well as areas that needed improvement. GM engineers have also done their best to keep the C6 competitive, and their ministrations have yielded consistent, meaningful improvements over the vehicle's model run. In our opinion, the current Corvette is the best sports-car value in the world. What follows is an overview of its evolution.
A Solid Foundation
The C6 had big shoes to fill following the success of the C5. Chief Engineer Dave Hill and his team developed an innovative mechanical structure for the C5, and lead designer John Cafaro wrapped it all in a sleek aerodynamic body that drew crowds. Its foundation was a hydroformed steel frame that held the body structure in place during assembly. A front aluminum subframe secured the front suspension and brakes, steering rack, and engine, while a rear subframe held the rear suspension and brakes, differential, and transmission. The two assemblies were joined with a torque tube that held a driveshaft. The body and frame came together in a "marriage" on the assembly line, with four bolts in the front and four in the rear. The car was a true stunner that provided incredible performance for the money.
Hill, engineer Tadge Juechter, and the Corvette team worked closely with designer Peters to begin development of the C6 in 2000. The team's goal was to "tighten" the body design to make it smaller and more space efficient.
As a result, the C6 was five inches shorter (174.6 vs. 179.7) and one inch narrower (72.6 vs. 73.6) than the C5. The wheelbase was lengthened (105.7 vs. 104.5) to improve the car's ride, a change made possible by moving the front cradle forward. The C6's drag coefficient even improved slightly (to .28 from .29) over the previous car. Under the hood, the new 6.0L LS2 engine raised output by 50 horsepower over the 5.7L LS1, yielding figures of 400 hp and 400 lb-ft of torque. The C6 was lauded by the motoring press for its performance and styling. Corvette buyers apparently agreed, as sales for 2005 totaled 37,372 units.
The Z06 Returns
The Z06 returned to the lineup in '06 featuring an aluminum hydroformed structure, magnesium cradles, and lightweight carbon body panels. Thanks to these weight-saving efforts, the car tipped the scales at a mere 3,132 lbs. Among recent Corvettes, only the '04 Z06 Commemorative Edition, at 3,118 lbs, was lighter.
Stuffed inside this lightweight structure was a racing-derived 7.0L LS7 engine that produced 505 hp and 470 lb-ft of torque. Larger brakes, wheels, tires, and stretched front and rear fenders were also standard. Customers clamored to buy this new Corvette hot-rod, sometimes paying exorbitant dealer premiums for the privilege.
To help demonstrate the new ueber-Vette's racing mettle, Chief Engineer Hill sent six "Captured Test Fleet" Z06s to Europe to be converted into race cars. Callaway Competition in Leingarten, Germany, promptly built them into Z06.R GT3 racers and turned them loose on road courses across the continent. Since then, a total of 23 have been constructed, and these cars have won multiple FIA GT3 championships.
Other big news for '06 included the introduction of a new six-speed automatic transmission with steering-wheel-mounted paddle shifters. On the personnel front, Dave Hill retired after spending 12 years as Corvette's chief engineer, handing the reins to Tadge Juechter. Tom Wallace, meanwhile, assumed the title of Vehicle Line Executive, a position from which he would also oversee the Corvette-based Cadillac XLR.