Future Car Trends: 2008 Corvette: New 436hp 6.2L LS3 Engine

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.

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.

Exhaust system – Optional on ’08 Coupe and Convertible models is a new, two-mode performance exhaust system. Similar in design and function to the system used on the Z06, the dual-mode exhaust uses vacuum-actuated outlet valves, which control engine noise during low-load operation, but open for maximum performance during high-load operation. It is not identical to the Z06 system; the Coupe/Convertible uses a 2.5-inch-diameter exhaust, while the Z06 uses a three-inch system.

With the new, dual-mode performance exhaust, power output for Coupe/Convertible rises from 430 horsepower (321 kW) and 424 lb.-ft. of torque (575 Nm) to 436 horses (325 kW) and 428 lb.-ft. (580 Nm). This system gives the Corvette a more aggressive exhaust sound character that will appeal to performance enthusiasts.

Transmissions and axle ratios – The shifting efforts for both the six-speed manual transmission and paddle-shift six-speed automatic transmissions have been improved in ’08 Corvette models. The manual transmission shifting improvements include a more positive and direct feel during gear changes, with better gate-to-gate location.

The six-speed paddle-shift automatic transmission on Coupe and Convertible is improved with new hardware and a new controller calibration that deliver quicker shifts. This change bolsters the feeling of performance and driver control when using the shifting paddles.

Also new for ’08 models is the availability of the 2.73 performance axle ratio with the automatic transmission. It is included with the Z51 package.

Steering system – The Corvette’s precise rack-and-pinion steering system is revised to provide improved feel at all speeds. The revisions are due to a new, premium machining process of the system’s internal components, a new, stiffer intermediate shaft and controller calibration changes.

Wheels – Corvette Coupe and Convertible models come with a new split-spoke wheel design for ’08. The design was introduced on the limited-edition ’07 Indianapolis 500 Pace Car replicas with a Sterling Silver finish. The standard 18-inch front wheels and 19-inch rear wheels feature a Sparkle Silver finish, with a Competition Gray version optional.

Also new is a distinctive, performance-oriented forged aluminum wheel for Coupe and Convertible. It comes in a polished finish.

Exterior colors

There are two new premium exterior colors available with 2008 Corvette models: Jetstream Blue Metallic Tintcoat and Crystal Red Metallic Tintcoat; they replace Le Mans Blue Metallic and Monterey Red Metallic Tintcoat.

Custom Leather-Wrapped Interior Package – Available on Coupe, Convertible and Z06 models, the new Custom Leather-Wrapped Interior Package offers a stylish, two-tone leather-appointed cabin with details that enhance the feeling of Corvette’s craftsmanship. Details include:

Two-tone, leather-wrapped upper and lower instrument panel, door pads and seats
Choice of new, exclusive colors: Linen or Sienna, with unique color breakup
Padded door panel armrests
“Corvette” embroidered on passenger-side dash pad
Embroidered crossed flags logo on headrests
Unique center trim plate with Bias pattern.

Interior enhancements

All models feature a new wrapped instrument panel center trim plate, with bright surrounds for the shifter and cupholder. There are also new metal-finish door sill plates that greet passengers as they step into the vehicle, as well as a new lighted control knob for the available Magnetic Selective Ride Control.

Feature changes and enhancements – All Corvette models now come standard with features that were previously optional or part of equipment packages. They include:

OnStar with available Turn-By-Turn Navigation
XM Satellite Radio
Auto-dimming rearview mirrors (with compass)
Audio input jack on all radio systems except navigation; Personal Audio Link is available as a dealer-installed item with the navigation system.

The ’08 Corvettes also come with a new Keyless Access fob, which features the key and remote-function controls integrated in a single unit.