2008 Chevrolet Corvette
(from General Motors Press Release) Get comfortable. There’s so much new and exciting with the 2008 Corvette that you’ll want to grab a hot drink, sidle up to your computer screen and absorb all the details.
The changes involve everything from an all-new, larger and more powerful V-8 engine to refinements in driving characteristics that solidify the Corvette’s position as the preeminent American sports car – and further the argument that it is one of the world’s best. There are also a host of exterior and interior refinements that raise the Corvette’s luxury status and enhance the feeling of craftsmanship.
“Corvette is an uncompromising sports car that rewards its owners with impeccable performance and great comfort,” said Ed Peper, Chevrolet general manager. “The changes and enhancements to the 2008 Corvette reflect continual improvements that speak to Chevrolet’s unflagging commitment to building the best sports car – and with nearly 55 years of experience, the Corvette just keeps getting better and better.”
Also back again for ’08 is the 505-horsepower Corvette Z06, an American super car that has won over enthusiasts, journalists and racers around the world for its balance of racetrack-bred performance, daily-driving civility and value.
Here’s a look at the new and enhanced features for ’08 Corvette models:
Engine – A new, 6.2L LS3 small-block V-8 is the standard engine in Coupe and Convertible models. It is rated at 430 horsepower (321 kW)* and 424 lb.-ft. of torque (586 Nm)* with the standard exhaust system; with the new, optional two-mode exhaust system, power ratings increase to 436 horses / 325 kW and 428 lb.-ft. / 592 Nm. As a result, the standard Corvette is true supercar, capable of 190 mph. The LS3 with the six-speed paddle-shift automatic is the fastest automatic-equipped Corvette ever, with 0-60 mph capability of 4.3 seconds.
This new iteration of the storied small-block family features a revised, larger-bore cylinder block – 4.06-inch / 103.25 mm vs. the previous 6.0L’s 4.00-inch / 101.62 mm bores – high-flow, LS7/L92-style cylinder heads; larger-diameter pistons; revised camshaft and camshaft timing; revised valvetrain with offset intake rocker arms; high-flow intake manifold; high-flow fuel injectors from the Z06’s LS7 engine; and a new engine beauty cover.
The LS3 features an aluminum cylinder block with cast iron cylinder liners. In addition to its larger bores, which help create a 376-cubic-inch displacement, the block casting also features revisions and machining in the bulkheads that enhance its strength and improved bay to bay breathing. But while the bore of the 6.2L engine is increased when compared with the previous 6.0L engine, the engine’s stroke remains at 3.62 inches (92 mm). The pistons for the larger 6.2L engine also are new and are designed for its high-rpm performance capability.
Breathing for the new 6.2L engine is accomplished via new, high-flow cylinder heads. They’re based on the large port/large valve design found on the LS7 engine and other GM L92 engines, with larger-capacity, straighter intake ports. The design optimizes intake flow to the combustion chamber and the exhaust ports are also designed for better flow.
Complementing the larger-port design of the heads are commensurately sized valves. The intake valve size alone increases from 2.00 inches (50.8 mm) to 2.16 inches (55 mm) – an increase of nearly 9 percent. The intake valves feature lightweight hollow stems, which enable the engine’s 6,600-rpm capability. The exhaust valves also are large, measuring 1.60 inches (40.4 mm) in diameter.
To accommodate the engine’s large valves and enable more direct intake port flow, the intake-side rocker arms are offset 6 mm between the valve tip and the push rod. Actuating the valves is a new camshaft, with intake-side lobes providing more than a 5-percent percent in increase in lift, from 0.521-inch to 0.551-inch (13.25 mm to 14 mm). Exhaust-valve lift remains unchanged from the LS2. The camshaft timing was revised to optimize performance with the higher-lift intake cam profile.
Ensuring the cylinder heads receive all the air they can handles falls to a new, acoustically tuned intake manifold. The composite design is manufactured with a “lost core” process that improves runner to runner variation and reduces airflow losses. An acoustic foam material is used to reduce radiated engine noise; it is sandwiched between the outer top of the manifold and an additional “skull cap” acoustic shell. Also new beauty covers atop the engine shield the rocker covers and also feature a noise-reducing, acoustically tuned insert to provide a more refined engine sound.
