Corvette gets 650 horses

The all-new 2015 Corvette Z06 is the most powerful production car ever from General Motors and one of a few production cars available in the United States that delivers more than 600 horsepower.

The Z06’s LT4 supercharged 6.2-litre V8 engine is SAE-certified at 650 bhp (485 kW) at 6,400rpm and 881Nm of torque at 3,600rpm.

“The LT4 Small Block sets a new benchmark for power and torque at GM Powertrain Engineering.

“The engine also puts the new Corvette Z06 on par with the most powerful supercars offered in America, while delivering performance with impeccable manners that make it suitable for daily driving.”

Compared with other supercar engines, the LT4 is a veritable fountain of low-end torque, producing 619Nm just off idle and 847Nm by only 2,800rpm. The V12-powered Ferrari F12 Berlinetta, for example, produces about 28 percent less torque than the Z06, despite offering about 12 percent more horsepower – and its peak torque isn’t achieved until 6,000rpm.

The LT4 maintains 90 percent of its peak torque, or 802Nm, from 2,500 to 5,400rpm.

The new LT4 engine eclipses the Porsche 911 Turbo S engine’s peak power levels by 90 horsepower (67 kW) and 182Nm of torque.

“Torque is the pulling power of an engine, and the LT4’s abundance of it at every rpm in the engine’s speed range helps the 2015 Corvette Z06 accelerate quicker and respond nearly instantaneously,” said Jordan Lee, chief engineer for Small Block engines. “It’s the very definition of power on demand.”

The new Z06 engine produces 40 percent more peak torque (244 Nm) than the previous-generation’s 7-litre LS7 engine – and 7.5 percent more than the supercharged 2013 Corvette ZR1’s 819Nm.

At 3,200rpm, the new LT4 surpasses the LS7 by 252 Nm. On the horsepower side of the graph, the LT4’s 485kW rating is 29 percent greater than the LS7’s 376 kW, and 9kW more than the ZR1’s LS9 engine.

LT4 details

The new LT4 engine is based on the same Gen 5 small block foundation as the Corvette Stingray’s LT1 6.2-litre naturally aspirated engine, incorporating several unique features designed to support its higher output and the greater cylinder pressures created by forced induction, including: heads that are stronger and handle heat better than conventional aluminum heads.

steel connecting rods for reduced

reciprocating mass.

forced-induction engine – enhances performance and efficiency and is enabled by direct injection. stronger structure to ensure strength under high cylinder pressures. an aluminum balancer that are lighter than their LT1 counterparts. a dual-pressure-control oil pump. A new 1.7-litre supercharger spins at up to 20,000rpm – 5,000rpm more than the supercharger on the Corvette ZR1’s engine. The rotors are smaller in diameter, which contributes to their higher-rpm capability – and enables them to produce power-enhancing boost earlier in the rpm band.

That boost is achieved more efficiently via a more direct discharge port that creates less turbulence, reducing heat and speeding airflow into the engine.

“The Small Block’s cam-in-block design heritage has always enabled very high performance and responsiveness in a small, compact package – an attribute amplified by the performance of our new supercharger’s design,” said Lee.

The LT4 is assembled at the new Performance Build Centre at GM’s Bowling Green Assembly Plant and at GM’s Tonawanda engine plant in New York, USA. It is matched with a standard seven-speed manual transmission or an all-new, paddle-shift eight-speed automatic transmission built in Toledo, Ohio.

Designed to deliver shift responses on par with the world’s best dualclutch transmissions, it is the first automatic offered in a Z06. It also makes the Z06 one of the few cars this powerful to offer the choice of a conventional manual transmission or an eight-speed automatic.

The 2015 Corvette Z06 goes on sale in the US in the fourth quarter of 2014.