A lightweighting strategyâusing materials including carbon fiber composites,
aluminum, and magnesiumâis used for the Corvette Z06, a car that you can do
this withâor that you can drive to the store in to pick up a gallon of milk.
The Z06 has an LT4 V8 under its composite hood, a small-block engine that has
massive performance, as in 650 hp and 650 lb-ft of torque. It has an aluminum
block and heads.
Related Topics:
- Automotive LIghtweighting
- Automotive Materials
You might think that if you have a supercharged, 6.2-liter V8 engine under the hood, an engine that is SAE-certified at 650 hp and 650 lb-ft of torque, mass is probably not too much of an issue: after all, there is all that power to move the car with alacrity.
But the engineers who worked on the 2016 Corvette Z06, the most power-ful production car that General Motors has ever built, made sure that they were frugal when it came to adding grams of mass to the vehicle.
Ostensibly, there were two key themes used in the development of this version of the Corvette: minimize mass, maximize performance.
The hood is carbon fiber. There are carbon fiber aero packages available for the car, which include a carbon fiber front splitter with aviation-style winglets (the Z07 package features larger winglets), carbon fiber rocker panels, and a rear spoiler.
While grille mesh is ordinarily a design feature, the mesh for the Z06 makes a difference to the performance of the vehicle, as it is designed to deliver the maximum amount of airflow into the superchargerâs intercooler heat exchangerâin fact, the mesh pattern used does a better job of managing airflow than would be the case were the entire grille simply removed. (To get rid of that air, there is a large hood vent: were that air to be channeled under the car, thereâs the danger that it would create lift; an objective of the program development was to create as much downforce as is practical; the car is said to have the most downforce of any production car GM has tested.)
The structure of the Z06 is aluminum, and it is so stiff that it isnât necessary to add structural reinforcements to accommodate a convertible model of the Z06. The non-convertible version has a removal carbon fiber roof panel. With the panel installed, the structure is 60% stiffer than the previous-generation fixed-roof Corvette. With the panel removed, it is still 20% more structurally rigid.
There are two types of seats available (GT for everyday driving; Competition Sport for those so inclined to take advantage of the carâs capabilities [e.g., 0 to 60 mph in 2.95 seconds with the eight-speed automatic; lateral acceleration of 1.2 g; 60 to 0 mph braking in 99.6 ft.]); both seat types feature magnesium frames. (It is probably worth noting that in addition to carbon fiber interior trim there is a steel-reinforced grab bar on the edge of the center console for the passenger.)
The LT4 engine in the Z06 is based on the Gen 5 small block thatâs used in the Stingrayâs LT1 6.2-liter naturally aspirated engine, yet it has been cleverly engineered to produce 650 hp, significantly more than the LT1âs 455 hp (460 hp with a performance exhaust package).
The LT4 engine features Rotocast A356T6 aluminum cylinder heads; the casting process, which uses centrifugal force to move the molten metal into the mold, produces heads that are more capable of handling heat than conventional aluminum heads. The intake valves are titanium. The connecting rods are machined, forged power metal steel. There are forged aluminum pistons that have polymer-coated skirts to prevent bore scuffing. The exhaust manifolds are stainless steel. There is an aluminum balancer.
The supercharger was designed to be more compact than is typically the case. This compact unitâan assembly that combines the supercharger and the intercoolerâfits within the valley between the cylinder heads. This means that the LT4 engine in the Z06 is 25 mm taller than the LT1 engine in the conventional Corvetteâbut it also provides some 37% more horsepower and 40% more torque (remember: performance and mass).Â
The eight-speed transmission, the 8L90, is engineered so that it fits within the same package space as the six-speed transmission used in the Corvette Stingray. The 8L90 makes extensive use of aluminum and magnesium in its construction. Consequently, it is 4-kg lighter than the six-speed.
Curb weight for the Corvette Z06: 3,524 lb.Â