Pasting legendary option codes onto new model offerings may be common practice in the automotive world, but it’s not often that these “reborn” versions live up to the promise of their storied appellations. Corvette is something of a happy exception in this regard, as successful modern-day relaunches of the Grand Sport (in 1996), ZR-1 (in 1990), and Z06 (in 2001) amply demonstrate. Of this historically obeisant troika, it is the latter car that has arguably had the greatest impact on the overall direction of the marque, thanks to its unique blend of technological innovation and real-world accessibility. Titanium engine and exhaust hardware, six-piston front brakes, carbon-fiber body panels—all race-spec kit offered for the first time on Corvette in various iterations of the street-going Z06, and at a fraction of the price of competitive makes. The C8-based version, introduced to the public in late October, looks poised to continue that tradition, and to further hoist the already-lofty bar for Z06 performance along the way.
We’ve discussed the car’s tortuous path to production at length in previous issues, so we won’t recapitulate it here. Suffice it to say that, having overcome multiple production challenges stemming from the COVID pandemic, the new Z06 will finally start rolling into dealerships this summer as a 2023 model. No official pricing information was available as we went to press, but we fully expect Corvette’s new performance standard-bearer to continue in the tire tracks of its predecessors by offering supercar performance at a supersize discount. Look for a base MSRP of around $90,000, with highly optioned examples creeping past—and maybe well past—the $100K mark.
For that sum, buyers will receive a technological tour de force of the kind not seen since the C4 ZR-1 debuted to considerable fanfare more than three decades ago. But whereas the original “Corvette From Hell” was powered by an innovative 5.7-liter V-8 designed in part by British firm Lotus, the Z06’s Hades-hot LT6 mill was developed entirely in-house at Chevrolet. Moreover, the LT6’s signature piece of hardware—a flat-plane crankshaft—is a thoroughly exotic item more commonly associated with full-on racing engines, and those responsible for its inclusion on the new engine are keen to underscore that fact.
“There was a niche following [among Corvette enthusiasts] that pined for a naturally aspirated engine that would exceed the power of the previous-generation supercharged engine,’ said Corvette Executive Chief Engineer Tadge Juechter said during the Z06’s October intro. “The only way to achieve that was to do the highest-output naturally aspirated V-8 that’s ever been done in automotive history.”
That output—670 horsepower at a dizzying 8,400 rpm—does indeed give the 5.5-liter LT6 a 20-horse edge over the C7 Z06’s blown, 6.2-liter LT4, though its torque figure of 460 lb-ft of torque at 6,300 revs falls well short of the LT4’s 650 lb-ft. Still, the new car is claimed to out-accelerate its forebear by a comfortable margin, thanks to a slightly lower curb weight (3,434 pounds with the optional carbon wheels) and the traction advantage offered by its mid-engine powertrain layout. In fact, Chevy says the ’23 Z06 will explode to 60 mph in just 2.6 seconds from a dead stop, making it quicker in that measure than not only the C7 Z06, but the 755-hp ZR1 variant as well. Quarter-mile times should clock in at well under 11 seconds, with some early projections putting the figure as low as 10.6 clicks.
A Racecar for the Street
This author dedicated his December ’21 editorial column (“Flat Demand”) to the features and advantages of a flat-plane crankshaft, so we won’t delve as deeply into them here. But in practical terms, a flat-plane crank allows for quicker revving and the ability to attain, and maintain, higher rpm levels than would be possible with a traditional, cross-plane unit. When you stop to consider that the LT6’s redline of 8,600 rpm is a full 2,000 revs higher than that of the old LT4, it’s possible to discern the type of driving experience Corvette engineers were shooting for with the new Z06.
“It has all of those feelings of the [C8.R] racecar,” reports retired Corvette Racing driver (and current GM consultant) Oliver Gavin, a man who knows of what he speaks. “The gap between the racecar and the road is getting smaller and smaller.”
While Chevy has long used the term “technology sharing” to burnish the Z06’s performance cred, the connection between the road-going car and its race-only counterpart has been tenuous at times. But the ’23 edition, a version of whose LT6 mill has been howling its way to victory in IMSA GTLM competition for nearly two years, is unquestionably the real deal.
In addition to its much-ballyhooed crank, features contributing to engine’s race-ready deportment include a few we’ve seen in Z06s before—e.g., dry-sump oiling, CNC-machined combustion chambers, forged pistons and rods—and others we haven’t. The LT6’s dual overhead-cam configuration marks the first deployment of such a valvetrain layout in a Corvette street car since the C4 ZR-1’s LT5, while its compression ratio checks in at an L88-matching 12.5:1. Each engine is hand-assembled in the Performance Build Center in Bowling Green, then fitted with a plaque bearing the name of the single technician who pieced it together from start to finish.
The Stingray’s TR-9080 eight-speed, dual-clutch transmission (DCT) is retained, but fitted with a lower, 5.56 final-drive ratio to further sharpen the Z06’s acceleration and throttle response. GM’s fourth-generation Magnetic Ride Suspension is also carried over from the base car, albeit as standard equipment and with a Z06-specific calibration.
Interestingly, given all this talk of motorsports influence, early versions of the C8 Z06 weren’t quite racy enough in one important respect: They were too quiet inside. To overcome this, engineers devised unique “reverse megaphone” exhaust tips that reflect sound off of parabolic surfaces on the car’s rear bodywork, and toward the cabin occupants’ ears. “It looks like a regular, old exhaust system,” said Juechter, “but there’s a ton of science in it.”
Aggressively bulged fenders have been a Z06 hallmark since 2005, and the C8 version carries that tradition forward. The front and rear panels are 30 and 40mm wider, respectively, than the Stingray’s, freeing up room for 20×10- and 21×13-inch wheels encased in standard 275/30ZR20 and 345/25ZR21 Michelin Pilot Sport 4S ZP tires. Opting for the full-bore Z07 package (sidebar) substitutes Sport Cup 2 R ZP rubber developed specifically for the Z06.
Intakes in the Z06’s front fascia channel air to a center heat exchanger, one of five such devices fitted to the car. Working in tandem with enlarged rear cooling scoops, they should help ward off the heat-soak issues that plagued some track-driven examples of the supercharged C7 edition.
As with the 2015-19 Z06, the ’23 model offers two levels of aerodynamic trim. Standard Zs receive a front splitter and a rear spoiler with a removable wickerbill that creates an additional 365 pounds of downforce at 186 mph. An optional carbon-fiber package ups the ante considerably with a larger splitter, front dive planes, a pedestal-mounted rear wing, and underbody aero “strakes.” It also makes for a far more dramatic-looking car, something to keep in mind if you’re intent on standing out from the Stingray hoi polloi.
A similar “tiered” approach carries over to the Z06’s brakes. The base car gets Brembo rotors measuring 14.6 inches up front and 15.0 inches in the rear; they’re clamped by six- and four-piston calipers, respectively. RPO Z07 swaps in even larger rotors made from fade-impervious carbon ceramic.
Alterations to the C8’s already excellent interior are limited to material upgrades, specifically a choice between two levels of carbon-fiber trim or a new Stealth Aluminum treatment. Factor in all the available color, seat-style, stitching, and seatbelt choices for ’23, and you have the ability to customize the Z06’s cabin in virtually any fashion imaginable.
Considering all the “giant leap” improvements embodied in the new Z06, it’s easy to overlook one of the car’s subtler—but, we suspect, no less significant—features: tiny rocket-ship logos cast into various spots on the LT6 engine. The symbolism presumably is not lost on GM President Mark Reuss, who during the intro event likened the car’s development process to “going to the moon,” adding, “We’re just getting started.”
With even more advanced models such as the E-Ray and “Zora” hypercar reportedly in the offing, it’s clear that the C8’s journey into the performance stratosphere will be an exhilarating one. m