Marking the sixth generation of its legacy, the 2005 Chevrolet Corvette delivers more power, passion and precision to reach a new standard of performance car excellence.
The sixth generation Corvette blends technical sophistication with expressive style. Five inches shorter than the current car, the 2005 Corvette cuts a tighter, more taut profile – with virtually no loss of usable space. More than just visual, the new dimensions make the car more agile and “tossable,” with upgrades in handling, acceleration and braking. At 0.28 coefficient of drag, the C6 is the most aerodynamically efficient Corvette ever and has improved anti-lift characteristics that enable improved high-speed stability and confidence.
A new LS2 6.0-liter small-block V-8 is the standard engine in the 2005 Corvette C6. It is based on GM’s new Gen IV small-block family of engines. The LS2 raises the bar for standard performance in the Corvette, delivering estimated peak output levels of 400 horsepower and 400 lb.-ft. of torque. It is the largest, most powerful standard small-block engine ever offered in Corvette. Cylinder heads for the LS2 are derived from designs used in previous Corvette Z06 models, including raised intake ports and an unshrouded-valve combustion chamber design that, when combined with the engine’s flat-top pistons, produces a more efficient swirl of the air/fuel mixture. This efficiency enables a higher 10.9:1 compression ratio, which increases fuel economy and horsepower. To beef up the internals, a five-pinion planetary gear set was added – replacing a four-pinion gear set. The extra gear reduces friction and loads carried by all the gears. The washers between the gear sets are made from Teflon, allowing optimal operation at high speed. For protection from the high temperatures that are generated by high speed, a four-plate oil cooler has been added. When the transmission fluid reaches 127 degrees Celsius (approximately 260 F), the torque converter lock does not disengage, except briefly during shifts. This prevents fluid shear in the torque converter from adding heat to the transmission.
Advances in catalyst substrates made possible catalytic converters that are at the same time more effective and less restrictive for the LS2’s exhaust. The new converters are mounted closer to the exhaust manifold for quicker lightoff and reduced cold-start emissions. As a result, the more restrictive quad catalyst design of the LS1 – with its small, auxiliary “pup” converters – was not necessary to meet emissions requirements. An additional benefit of the exhaust system’s development was the elimination of the LS1’s air injection reaction system. Subtle adjustments were made to the C6 exhaust system itself to improve its performance. Sharp angles in the tubing have been replaced with more gradual bends. A larger muffler volume and tri-flow technology eliminated certain periods prone to unwanted noise, particularly between 1500 and 2400 rpm. An inline muffler that flows more efficiently replaces the laterally mounted muffler in the C5. These changes, coupled with one converter per exhaust bank, reduced backpressure in the system and contributed to the LS6’s 400 horsepower and 400 lb.-ft. of torque.
Major revisions to the manual and automatic transmissions provide Corvette with significant improvements geared towards performance driving. The Tremec six-speed manual gearbox is available with two sets of ratios, one with more aggressive acceleration characteristics reserved for Corvette’s Z51 Performance Package that emulates the performance of the C5’s landmark Z06 model. Improved shifting characteristics are another major improvement, with new synchronizers that reduce travel by 10 percent, and a shifter knob that is an inch shorter and redesigned for greatly improved driver operation. The Hydra-Matic 4L65-E automatic transmission is an upgraded version of the C5’s 4L60-E, strengthened and revised to accommodate the LS2’s 400 lb.-ft. of torque. It includes GM’s advanced Performance Algorithm Shifting, which automatically selects the optimal gear for a given driving condition, making it a willing accomplice for performance driving and hard cornering. The transmission now shifts at higher revs to take advantage of the higher engine output. Not only does the LS2 engine deliver impressive horsepower, but in a true measure of real-world efficiency, it also boasts the best combination of horsepower and fuel economy among the world’s best performance cars.
None of the suspension bits has been carried over from C5. The short-long arm and transverse leaf spring independent suspension configuration remains, but the cradles, control arms, knuckles, springs, dampers, bushings, stabilizer bars, and steering gear are all redesigned. The Extended Mobility Tires (EMT) also are new, taking advantage of the latest sidewall design and compound technology for run-flat capabilities, and play a critical role in the tuning of the suspension for excellent handling and comfortable ride. Improvements in ride and handling include greater lateral acceleration, more body control, less noise transmitted from the road, and better traction and stability in corners. The specific tuning changes in the chassis and suspension include suspension and steering geometry optimized for better handling and ride, advanced compounds in the tires, new directional control arm bushings, increased caster angle and greater suspension ride travel. The result is a Corvette that is more poised at even higher handling levels, yet easier to drive.
Goodyear is supplying two different tires, depending on the suspension package. For the Standard and F55 Magnetic Selective Ride Control suspensions, a standard directional-tread tire is offered for a balance between handling and ride. The Z51 Performance Package – the choice for the serious enthusiast – features an asymmetrical-tread tire that offers maximum handling performance. The wheel and tire sizes are the same for the Z51 option, which will deliver handling abilities similar to the 2004 Z06, despite the slightly narrower width of the new tires.
With its increased horsepower and top speed, heartier braking is critical to C6’s overall balance of performance. The brake systems have been re-engineered from the previous generation Corvette to provide improved durability and excellent performance. The C6 brake system focuses its improvements chiefly on heat dissipation and durability requisite of the car’s upgraded overall performance capability. For the Standard and F55 Magnetic Ride configurations, the brake rotors remain the same diameter as the C5, at 12.8 inches in front and 12.0 inches in the rear. However, the rotors themselves have been thoroughly redesigned. The front rotors weigh 2 pounds more than the C5, aiding durability. They also generate less heat against the brake pads, which improves wear and reduces fade. In all brake applications, the front calipers utilize dual pistons and the rears use single pistons. The Z51 Performance Package extends the Corvette’s braking capability with larger diameter rotors (13.4 inches in front and 13.0 inches in rear) that are cross-drilled.
Three standard dynamic chassis control systems – anti-lock braking, traction control, and Active Handling – operate in concert to provide a strong, but unobtrusive safety net for spirited driving. In keeping with Corvette’s performance heritage, and unlike more intrusive systems of some competitors, the Corvette Team developed a calibration philosophy based on how Corvette drivers actually drive their cars. The C6’s dynamic chassis control systems are smarter, less intrusive, and more adept at making the total driving experience precisely what Corvette owners have come to expect from their car.
Gm.com © 2004