The C8 Corvette Z06 Is More C8.R than Stingray

After two years of watching the Corvette Racing C8.R dominate the track, General Motors has finally pulled the cover off a proper roadgoing variant. That car is the new C8 Corvette Z06, which shares a similar 5.5-liter flat-plane V-8 engine with the C8.R, known as the LT6. And while that 670-hp piece of naturally-aspirated art deserves much of the attention, the new Z06 also packs plenty of racing pedigree under the bodywork. In order to learn more, Road & Track sat down with the people behind the new Z06 to further discuss the improvements made to the car’s chassis.

The C8.R has raced its entire career with what is essentially a Z06 chassis underneath it, according to General Motors. The two cars were co-developed from the start alongside the Stingray, and the platforms are so similar that GM has referred to the C8.R as a Z06 hidden in plain sight. Considering the success that Corvette Racing has had during that time, the Z06 appears to have quite robust underpinnings. However, despite that serious increase in engine performance brought by LT6, the C8 Z06 doesn’t actually feature any additional chassis bracing compared to the Stingray. As GM’s lead development engineer of performance cars, Aaron Link explained in an interview with Road & Track that this is due to the fact that the C8’s rigid center tunnel was designed with future high-performance models in mind. This is also why the convertible Z06 model won’t require any unique chassis tuning, as the platform remains just as rigid as the coupe.

All C8 Z06 models also retain the same SLA-type front and rear suspension layout as the Stingray, though not without some improvements. As development of the Z06 got underway, GM quickly discovered that the mid-engined platform responded well to much higher spring rates than the older models, particularly up front. In fact, Corvette chief engineer Tadge Juechter confirmed that this new Z06 is the first Corvette to ever utilize a low-rate helper spring in the suspension system. This additional spring helps the car’s tires drop a bit farther under full rebound, which was initially an issue caused by the high spring rates. While it may seem easier to ease off the springs a bit, Link argues it was important to maintain the high spring rate in order to give the LT6 engine a complementary chassis.

More specifically, Link noted that GM wanted to match the sharp throttle response of the LT6 with a chassis that is equally as quick to change directions. That said, this setup also required the team to rework the rubber bushings inside the suspension system. The lower bushings are now made of a much stiffer rubber, while the upper units have been replaced by what GM is calling a slipper bushing. According to Link, this rubber piece behaves more like a ball-joint than a typical bushing, but without all the ride penalties and reliability concerns. This is yet another first for the Corvette lineup.

Every Z06 will also come with GM’s Magnetic Ride Control 4.0 dampers, though Z07 package-equipped models will receive a unique calibration. Different calibrations aren’t required for the different wheel options, however, as the system is able to adjust to the difference in unsprung weight. Speaking of the wheel options, the Z06 will be offered with both aluminum and carbon-fiber wheels, measuring 20 inches up front and 21 inches out back. Buyers will have a choice of five finishes on the aluminum units. The carbon wheels are supplied by the team at Carbon Revolution; they save a total of 41 pounds of unsprung mass over the standard wheels. Juechter also notes that the rear wheels are the widest carbon units ever produced, which was required to fit 345-section tires out back. The front tires measure in at a 275-section, making this the largest wheel and tire combo ever to come fit to America’s sports car. The carbon wheels are not tied to the optional Z07 package and can be ordered on a base Z06 if you so choose.