The 2006 Corvette Z06 comprises an unprecedented level of capability and technology,
“The new Z06 is the dividend from competing so successfully in endurance racing,” said Dave Hill, Corvette’s chief engineer. “It combines the strong attributes of the new, sixth-generation Corvette with the spirit, technology and know-how from the race program to form an American supercar with outstanding credentials.”
The Z06’s new LS7 7.0L engines delivers 505 horsepower (377 kw) in an approximately 3,130-pound (1,420 kg) package – a combination that is expected to deliver 0-60 performance of less than 4 seconds, quarter-mile elapsed times of less than 12 seconds and a top speed of more than 190 mph on a racetrack.
Links between racing and the production Z06 are both direct and indirect, as the vehicle was developed in conjunction with the C6-R. The technology transfer includes the application of lessons that could only have been learned after countless laps of endurance racing – everything from suspension geometry to aerodynamics. What engineers developed in the Z06 is a totally unique vehicle that has powertrain, body structure and chassis system features that are distinct from other Corvette models. In fact, the Z06 has a different body structure compared to Corvette Coupe and Convertible.
The new Z06 has an unmistakable and aggressive appearance, with design cues that include:
The aerodynamics of the Z06’s exterior were shaped by the experiences of the Corvette racing program, where high-speed stability and cornering capability are paramount. And while the racecars use large rear wings, the Z06’s elevated spoiler provides sufficient downforce to balance the road-worthy front splitter without adversely affecting aerodynamic drag. The Z06’s Cd is .31.
For all its race-inspired functionality, the Z06 is designed to be a daily driveable high-performance vehicle. To that end, comfort and convenience are held to a very high standard. High-Intensity Discharge llighting, fog lamps, leather seating, dual-zone air conditioning, cabin air filtration and head-up display (HUD) with track mode and g-meter are standard.
The Z06 also has a revised gauge cluster that displays the Z06 logo on the 7000-redline tachometer and has a new readout on the oil pressure gauge to reflect the higher standard pressure of the dry-sump oiling system. And, like other 2006 Corvettes, the Z06 has a new, smaller-diameter 370-mm three-spoke steering wheel that provides a more agile, performance-oriented feel. The seats feature two-tone leather surfaces, with Z06-logo embroidery and contrasting stitching.
Z06 options include a Bose audio system with an in-dash six-CD changer, polished wheels, a telescoping steering wheel, heated seats, side air bags, a navigation system with GPS, universal home remote and XM Satellite Radio.
But for all its comfort, engineers did sacrifice a few components in the quest for lower weight and higher performance. Seat side bolsters are fixed and more supportive to better hold the driver when cornering and they weigh less. The passenger seat features manual controls, saving the weight of a power-adjust motor, and the Z06’s acoustic package is revised to reduce weight and allow more aural feedback of the powertrain.
The all-new LS7 in the ’06 Z06 reintroduces the 427-cubic-inch engine to the Corvette lineup. Unlike the previous 427 engine, which was a big-block design, the new 7.0-liter LS7 is a small-block V-8 – the largest-displacement small-block ever produced by Chevrolet and GM, and a tribute to its 50 years as a performance icon.
With 505 horsepower (377 kw) and 470 lb.-ft. of torque (637 Nm), it also is the most powerful passenger car engine ever produced by Chevrolet and GM. The LS7 is easily identified under the hood by red engine covers with black lettering. The LS7 shares the same basic Gen IV V-8 architecture as the Corvette’s 6.0-liter LS2, but it uses a different cylinder block casting with pressed-in steel cylinder liners to accommodate the engine’s wide, 104.8-mm-wide cylinder bores. Compared with the LS2, the LS7 also has a different front cover, oil pan, exhaust manifolds and cylinder heads – among many other components.
Internally, the LS7’s reciprocating components make use of racing-derived lightweight technology, including titanium connecting rods and intake valves, to help boost horsepower and rpm capability. The rpm fuel shut-off limit is 7000 rpm. The LS7’s details include:
One of the clearest examples of the LS7’s race-bred technology is its use of titanium connecting rods. They weigh just 464 grams apiece, almost 30 percent less than the rods in the LS2 V-8. Besides lightweight, which enhances high-rpm performance and rpm range, titanium makes the rods extremely durable.
The LS7’s CNC-ported aluminum cylinder heads are all-new and designed to meet the high airflow demands of the engine’s 7.0-liter displacement, as it ingests approximately 100 cubic feet more air per minute than the Corvette’s 6.0-liter LS2 V-8 – an 18-percent increase in airflow. Consequently, a hydraulic roller camshaft with .591/.591-inch valve lift is used to allow plenty of air to circulate in and out of the engine.
To ensure optimal, uninterrupted airflow, the LS7’s heads have straight, tunnel-like intake runners. Very large by production-vehicle standards – even racing standards – they are designed to maintain fast airflow velocity, providing excellent torque at low rpm and exhilarating horsepower at high rpm. The heads feature 70-cc combustion chambers that are fed by huge, 56-mm-diameter titanium intake valves. The lightweight titanium valves weigh 21grams less than the stainless steel valves used in the LS2, despite the valve head having 22 percent more area. They are complemented by 41-mm sodium-filled exhaust valves, vs. 39.4-mm valves in the LS2. To accommodate the large valve face diameters, the heads’ valve seats are siamesed; and, taken from experience with the engines of C5-R racecars, the LS7’s valve angles are held at 12 degrees – vs. 15 degrees for the LS2 – to enhance airflow through the ports.
The LS7 has a dry-sump oiling system designed to keep the engine fully lubricated during the high cornering loads the Corvette Z06 is capable of producing. An engine compartment-mounted 8-quart reservoir delivers oil at a constant pressure to a conventional-style oil pump pick-up at the bottom of the engine. The pressurized oil feed keeps the oil pick-up continually immersed in oil at cornering loads exceeding 1 g.
Oil circulates through the engine and down to the oil pan, where it is sent back to the reservoir via a scavenge pump. The large-capacity reservoir, combined with a high efficiency air-to-oil cooler, provides necessary engine oil cooling under the demands of the engine’s power output. With the dry-sump system, oil is added to the engine via the reservoir tank – which includes the oil level dipstick.
The LS7’s dry-sump system was developed and tested on racetracks in the United States and Europe , including Germany ’s famed Nürburgring. And while common in racing cars, the Corvette Z06 is one of just a handful of production vehicles – and the only production Corvette – ever to incorporate such a high-performance oiling system.
For more articles on the Z06 Corvette, check our Corvette home page for more information.