2008 Corvette C6 Coupe

Motoring Channel Staff - 3/May/2007

Detroit, USA — If you find it hard to tell the difference between the newly launched 2008 American model Corvette and its precursors, you're not alone. The car looks very similar to the 2005, 2006, and 2007 models 'Vettes, but the big difference in 2008 is the new engine.

Instead of the LS2 6.0-litre V8 - the engine currently used in the some Holden VE Commodores and the high performance HSVs in Australia - the new 2008 C6 Corvette uses the new LS3 V8, which increases capacity to 6.2-litres and hikes power and torque levels respectively. 

The new small-block LS3 engine outputs 321kW (430hp) @ 5900rpm and 575Nm of torque @ 4600rpm, and buyers of the new 2008 model can specify a sports exhaust system that increases power to 325kW (436hp) and 580Nm respectively. 

With the power of the new Chevrolet LS3 V8 engine, the 2008 Corvette C6 Coupe charges from zero to 96km/h (0-60mph) in just 4.3 seconds with the automatic transmission, which makes it the fastest automatic-equipped Corvette ever according to Chevrolet. It weighs 1459kg, which isn't too heavy for an American sports car.

We asked the Australian-based HSV (Holden Special Vehicles), which has long used Corvette engine parts in its sports cars, if it would be switching the to the larger 6.2-litre LS3 power plant. Here is the response from HSV's spokesman: "There are are no plans to upgrade HSV models to the LS3 engine in the foreseeable future. The cars currently accelerate from zero to 100km/h in 4.9 seconds."

The new 2008 Corvette benefits from the LS3 engine, but Chevrolet has also made alterations to the car's driving characteristics that it claims solidify the Corvette's position as the preeminent American sports car – and further the argument that it is one of the world's best. 

"Corvette is an uncompromising sports car that rewards its owners with impeccable performance and great comfort," said Ed Peper, the general manager of Chevrolet. 

"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."

A new rack-and-pinion steering steering system has been added to the 2008 Corvette C6 that has been revised to provide improved feel at all speeds claims Corvette, and supplying the car with an altered image are new split-spoke wheel designs for 2008. The company explains the new wheel design was introduced on the limited-edition '07 Indianapolis 500 Pace Car replicas with a Sterling Silver finish measuring 18-inches in diametre at the front and 19-inches at the rear.

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.

All 2008 model Chevy Corvettes get metal-finish door sill plates, an audio input jack on all radio systems except navigation, a new back-lit control knob for the available Magnetic Selective Ride Control, OnStar with available Turn-By-Turn Navigation, plus XM Satellite Radio, auto-dimming rearview mirrors with compass, and a new Keyless Access key fob. 

Back again for the 2008 model year is the mad-as-a-cut-snake 376kW (505hp) Corvette Z06, which is powered by an axle crushing 7.0-litre V8 small block engine. Chevrolet says this American super car has won over enthusiasts, journalists and racers around the world thanks to its balance of racetrack-bred performance, daily-driving civility and value. 

The Z06 is super car quick, hitting 96km/h from standstill in 3.7 seconds which is quicker than both the Lamborghini Gallardo and Ferrari F430 - and completing the quarter mile run in 11.7 seconds with a speed of 125mph (201km/h).

Chevrolet LS3 Engine

According to Chevrolet, the latest iteration of the storied small-block family features a revised, larger-bore cylinder block (103.25mm [4.06-inch] vs. the previous 6.0-litre's 101.62mm [4.00-inch] bores that increases the capacity from 6.0- to 6.2-litre litres. Other changes include new 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; and high-flow fuel injectors from the Z06's LS7 engine.

In addition to its larger bores, explains Chevrolet, 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 6.2-litre engine is increased when compared with the previous 6.0-litre engine, the engine’s stroke remains at 92mm (3.62 inches). The pistons for the larger LS3 engine also are new and are designed for its high-rpm performance capability.

Breathing for the new 6.2-litre LS3 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 optimises 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 50.8mm (2.00 inches) to 55mm (2.16 inches) – an increase of nearly 9 percent. The intake valves feature lightweight hollow stems, which enable the engine's 6600rpm capability. The exhaust valves are large too, measuring 40.4mm (1.60 inches) in diametre.

To accommodate the engine's large valves and enable more direct intake port flow, the intake-side rocker arms are offset 6mm between the valve tip and the push rod. Actuating the valves is a new camshaft, with intake-side lobes providing more than a 5% in increase in lift, from 13.25mm to 14mm (0.521-inch to 0.551-inch). Exhaust-valve lift remains unchanged from the LS2 though the camshaft timing was revised to optimise performance with the higher-lift intake cam profile.

Ensuring the cylinder heads receive all the air they can handle, a new acoustically tuned intake manifold has been added. 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.

There is also a new Exhaust system that is optional on 2008 Coupe and Convertible Corvette models. It has two-modes of operation and is similar in design and function to the system used on the Z06. It uses vacuum-actuated outlet valves that control engine noise during low-load operation, but will open for maximum performance during high-load operation. In essence, when you're just cruising slowly the car makes less power and is quieter, but when you floor the gas pedal, the car will become louder and more powerful. Chevrolet says the system is not identical to the Z06 system because the standard 2008 Corvette uses a 2.5-inch-diametre exhaust, while the Z06 uses a larger three-inch system.

Peak power for the new 2008 Corvette C6 is 321kW (430hp) rising to 325kW (436hp) when the exhaust system opens up, and Chevrolet says this system gives the Corvette a more aggressive exhaust sound that will appeal to performance enthusiasts.

The shifting efforts for both the 6-speed manual transmission and paddle-shift 6-speed automatic transmissions have been improved for the 2008 Corvette models. The manual transmission shifting improvements include a more positive and direct feel during gear changes, with better gate-to-gate location, while the 6-speed paddle-shift automatic transmission is improved with new hardware and new controller calibration that deliver quicker shifts.

Also new for 2008 models is the availability of the 2.73 performance rear axle ratio with the automatic transmission (which is included with the Z51 package).

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- Chevrolet Captiva (2006)
- Chevrolet Camaro (concept)
- Chevrolet Corvette Z06 (2006)
- Chevrolet C6 Corvette (2005)
- Chevrolet Z06 Corvette (2003)