Chevrolet Corvette C6 ZR1

The Chevrolet Corvette C6 ZR1 is a high performance version of the Chevrolet Corvette C6. Both the C3 from 1969–1971 and C4 Corvettes from 1990-1995 had ZR-1 models. However, the C6 variant is officially labeled as the "ZR1" while previous variants had a hyphen between the ZR and 1, as in "ZR-1".
Components
Engine designThe Corvette ZR1 engine is a heavily modified version of the LS3, designated the LS9. Producing 638 hp (476 kW; 647 PS) and 604 ft·lbf (819 N·m) of torque, it is the most powerful production Corvette to date. The LS9 has a sixth-generation Eaton TVS R2300 roots 4-lobe supercharger with intercoolers from Behr, utilizing an air-to-water, dual-brick design. The supercharger's four-lobe design offers improved efficiency over three-lobe models. To avoid changes to the hood appearance, the supercharger's output was split into two halves. Each cylinder bank has an intercooler.

The cylinder walls of the LS3 are thicker than the Z06's LS7 since the LS3 has a smaller bore. Oil squirters under each piston help cool the pistons and cylinder walls are used for the first time in a production Corvette. Connecting rods and the inlet valve are made of titanium. Heads are made from a special heat resistant aluminum alloy. The camshaft lift was reduced from the LS7's to improve idle quality. With the addition of the supercharger to the 6.2 liter LS9, the higher lift camshaft was no longer necessary to achieve horsepower targets.

Lubrication is provided by an improved version of the LS7's dry sump system. The new system increases oil capacity from 8.0 to 10.5 quarts (9.94 liters). A new dual gerotor oil pump increases scavenge performance and oil pressure, enabling oil to be delivered under the most extreme conditions. Due to the increased pressure, the Ultraguard Gold UPF48R oil filter is required. The LS7 oilpan is used for the LS9 with the addition of an oil cooler which is mounted on the left side of the pan.

With the 2011 model, GM offers the optional "Corvette Engine Build Experience," where the customer visits the General Motors’ Performance Build Center to help assemble the LS9 for the ZR1 purchased. Factory technicians supervise the process and the normal warranty covers the engine built by the customer's hands.[1]
Transmission
The ZR1 flywheel has been improved over the 2008 Z06. The flywheel was upgraded by going from six to a nine bolt design and cutting off nearly 9.8 ounces (278 grams) for improved throttle response and acceleration.

The transmission is a 6-speed manual Tremec TR6060 with a MH3 gearset. The 2008 Z06 featured the MM6 gearset. Due to the gear ratios in the transmission and engine output, the ZR1 reaches top speed of 205mph in 5th gear, using 6th gear for gains in fuel efficiency at highway speeds.
Differential/drive
The differential is a limited slip with carbon and steel plates. The differential uses SAE 5W-80 Dexron LS lubricant.

The two half shafts have different diameters (33mm left, 40mm right), designed to prevent resonance during acceleration and reduce the chances of axle hop occurring.