The mid-engine Chevy Corvette’s new range-topping performance model has finally arrived. The 2023 Z06 packs a mind-blowing 670 horsepower by way of a 5.5-liter, naturally aspirated, flat-plane crank V8, making it the most powerful naturally aspirated V8 ever put into a production car. Period. And in case you’d forgotten, even the supercharged 2022 Cadillac CT5-V Blackwing offers just 668 ponies. Say hello to the new king of internal-combustion performance at General Motors.
“The new Corvette Z06 defines the American supercar,” said General Motors President Mark Reuss in the Z06 announcement. “It builds on the distinctive design and groundbreaking dynamics introduced with the mid-engine Corvette and elevates them to deliver refined but uncompromising track capability with world-class performance.”
This wider, faster, louder Corvette is offered with multiple aero packages from street-friendly to time-attack, carbon fiber wheels, carbon ceramic brakes and a completely overhauled chassis engineered to put all-out track performance front and center. Production of this new monster is expected to begin in summer of 2022.
Let’s dive in:
Sure, the LT6 V8’s 460 lb-ft of torque may pale in comparison to the Blackwing’s output, but it’s head-and-shoulders above the power output of the overhead-valve LT2 in the Stingray, which makes “just” 495 hp and 470 lb-ft. Plus, neither the LT2 nor the Blackwing’s monster LT4 winds out to anything approaching 8,600 RPM. In fact, peak power in the Z06 comes at 8,400. If your expectation for a V8 is a fat, wide tsunami of torque, this highly-strung breaker may not be your cup of tea. To lug this engine around would be to miss the entire point. Here it is, directly from Chevy:
“More than horsepower, the new LT6 is designed to complement all aspects of the Z06’s track-focused performance experience. From its 8,600-rpm redline and full racing-style dry-sump oiling system to meticulously tuned induction and exhaust systems, this engine exudes an entirely new and emotional character. The key to the LT6’s performance capability is a lightweight, low-inertia rotating assembly rooted in an all-new flat-plane crankshaft that, along with a comparatively short stroke (the distance each piston/connecting rod assembly travels with each rotation of the crankshaft), allows the engine to rev to its maximum range.”
“A version of the LT6 has powered the C8.R race cars since 2019, and the rigors of endurance road racing helped engineers refine the engine’s performance and durability.”
Translation? This is an engine that not only makes power up high, but was engineered specifically to operate at those speeds for extended periods of time. On a race track, engines are expected to operate almost exclusively at or near the peak of their powerband. This is where the Z06’s upgraded eight-speed dual-clutch transmission comes into play. The more gear ratios available to the engine, the more exploitable a peakier curve becomes.
The hand-assembled LT6 retains the 4.4-inch bore spacing common to Chevy’s small block engines, but you’ll struggle to find too many more similarities. The valvetrain is a complete departure, foregoing the tried-and-true (and compact) overhead valve packaging common to the small block family in favor of dual overhead camshafts. The pistons and connecting rods are forged; the intake valves are titanium and the exhaust valves sodium-filled. Track junkies will appreciate the return of a dry-sump oiling system.
There’s plenty to talk about outside of the engine bay too. While the standard C8’s basic chassis and suspension architecture carry over, many components have been beefed up or augmented, including the standard Magnetic Ride Control 4.0 adaptive suspension system. The base brakes are bigger, with 14.6-inch-diameter rotors up front and 15-inchers in the rear. The Z06’s base Brembos come with six-piston calipers; the standard Stingray gets four-pots.
The Z06’s wider fenders made room for larger, wider wheels and tires (20×10-inch front wheels wrapped in 275/30ZR20s and 21×13-inch rears with 345/25ZR21s) and widen the car overall by 3.6 inches. Michelin Pilot Sport 4S tires are standard, with Sport Cup 2s available with the Z07 package. The rest of the body was designed with similar functional upgrades. The larger openings in the front fascia feed beefed-up cooling systems for the engine and transaxle, with some air being diverted to cool the brakes as well.
Sticking with the body, even the standard Z06 comes with an adjustable rear spoiler to help drivers optimize its aero performance, but that’s just the tip of the iceberg. For those who want more, Chevy will offer two aero upgrade packages. The basic carbon fiber aero package adds a larger front splitter, front corner-mounted dive planes, a pedestal-mounted rear wing and underbody strakes to improve downforce. Above that is the Z07 package, which is where things really get nutty.
Z07 is the no-holds barred, I-belong-in-the-fastest-run-group version. This performance package includes the aforementioned Michelin Pilot Sport Cup 2 tires (custom-engineered for the Z06), an upgraded suspension with further recalibration of the standard Z06’s MRC 4.0 system, and Brembo carbon ceramic brakes with larger rotors. In fact, the Z07 package is the only variant of the Corvette that has larger rotors on the front axle (15.7″) than on the rear (15.4″). Chevrolet says the Z06 with the Z07 Performance Package can pull 1.22g of lateral acceleration on its 300-foot diameter skidpad.
Source: www.autoblog.com