The spec sheets reveal plenty of differences, but until you look at the a regular Chevrolet C8 Corvette Stingray parked beside the recently revealed 2023 Chevrolet Corvette Z06, you don’t realize how different they really are. The Z06 and its optional Z07 Performance package go beyond looks, too, as there are functional differences between it and the Stingray. We parked MotorTrend’s long-term C8 Corvette next to a new Z06 during a Chevy event at The Motoring Club in Marina del Rey, California, to get a live look at how the two cars compare.
Cooling the Z06
The front fascia is our first stop. The Z06’s center grille and side vents are not only drastically different but are also functional. Each of the side vents fronts a radiator, whereas our Stingray with the Z51 package only uses one for that purpose. The Z06’s openings are much larger and the fans behind them are more powerful, too. Inside the center grille edges are cooling ducts for the front brakes. A new fluid cooler is mounted dead center, and it’s part of Chevy’s “clean sheet approach with massive capacity increase to maintain low oil temperatures” for the LT6 engine.
According to Chevy, the Z06 utilizes a “bulk-cooling strategy.”
“On the Z06, the front three radiators work together to send coolant to the engine for cooling the block and heads,” said Chevy Communications rep Trevor Thompkins. “Prior to reaching the engine, some of the coolant tees off to the side radiators to stepdown the temperature of the coolant further before reaching the transmission and engine oil coolers, which are liquid-to-liquid heat exchangers.”
Stuck With Air
Improved aerodynamics are a huge part of the 2023 Corvette Z06, especially with the Z07 pack. However, the standard Z06’s primary aerodynamic pieces are a front splitter and underwing which add downforce. Interestingly for street driving, a gurney is installed on the underwing to stall the airflow and reduce drag while maintaining aerodynamic balance front to rear.
However, “For track driving,” Thompkins said, “the stall gurney is removed, allowing the underwing to generate more front downforce. In tandem with this stall gurney removal, the tall rear-spoiler wicker bill is attached to add rear downforce and balance the aerodynamics, resulting in a combined 365 pounds more downforce at 186 mph relative to the on-road configuration.”
You’ll also find the carbon-fiber aero package adds dive planes just ahead of the front wheel openings, and it includes aggressive carbon side sills.
The Z07 Aero Treatment
Indeed, compared to the regular Z06, much of the Z07 pack’s aerodynamic parts are enhanced with carbon fiber, including those front dive planes, a larger front splitter, underbody strakes, and a rear wing which replaces the spoiler.
To be clear, the carbon aero package is standard with the Z07 option, and Chevy says the whole shebang produces 734 pounds of downforce at 186 mph. That figure is “more than any Corvette ever and twice that of the standard Z06,” Thompkins said. If you have a standard Z06, you can add the carbon aero for an additional cost or select a Ground Effects Package that includes a larger front splitter and retains the wicker bill spoiler but no wing.
Fitting Bigger Tires
The overall width difference between the Corvette Stingray Z51 and the 2023 Chevrolet Corvette Z06/Z07 is 3 inches. You don’t really notice the extra width when looking at the Z06 by itself, but you sure see it when the car is parked next to the Stingray. The front fenders feature a crease where the standard Stingray fenders end; it adds 1.5 inches to each side. Despite this additional width, the mirrors on the Z06 and Stingray are the same, as are the rear camera packages.
You also don’t realize just how wide the new Corvette Z06’s front tires are until they are turned to expose their tread. These tires are massive and most likely won’t fit on the Z51 without the 1.5-inch extensions. The Z06’s rubber measures 275/30ZR20 in front, 345/25ZR21 in back. In comparison, the Stingray’s tires are sized 245/35ZR19 up front and 305/30ZR20 for the rear.
You’ll also notice the boomerang (or “blade”)—the trim piece that follows the side intake openings”—is shaped differently compared to the Z51’s boomerang.
The Back End
Walk behind the 2023 Chevrolet Corvette Z06 and you’ll notice the rear vents have changed. They aren’t as tall as the ones on the Z51, but they are much wider and are functional on the Z06. There is also a small extractor beside the rear bumper apron, and you’ll see the exhaust tips are no longer positioned on the corners.
Chevy moved the exhaust tips to the center of the rear apron, which also means the rear diffuser is different. As mentioned earlier, the rear wing is a functional spoiler with an interchangeable wicker bill on the standard Z06, while the Z07 and its carbon aero pack adds a carbon-fiber wing with a functional gurney flap. A final touch on the rear deck lid is the change from the stingray emblem to the Corvette flags, and the “CORVETTE” lettering is removed from the rear fascia.
DOHC Engine Fitment
You won’t notice the engine bay from outside of the car, and you won’t notice any difference when you pop the hood, either. The C8 was designed from the get-go with the new DOHC LT6 in mind.
“An additional clutch plate was added … to increase torque capacity, and the final drive ratio is now 5.56:1—shorter than the Stingray for more responsiveness,” Thompkins said. He also mentioned the transmission’s lubrication system is revised with a larger sump that makes it more effective in handling increased lateral loads. “Oil will not need to be added to the transmission as part of track preparation,” he said.
The exhaust manifolds have changed, too, for obvious and not so obvious reasons. “Tri-Y tubular exhaust headers reduce restriction and turn upward to route exhaust over the rear axle,” Thompkins said. The muffler was reworked to reduce restriction and improve sound quality, while rear-fascia-mounted bezels are shaped to help reflect some of the sound back to the driver.
When you hear the 2023 Corvette Z06’s engine start, you’ll notice it’s very loud then suddenly goes quiet. This is because the Z06 is fitted with a vacuum-controlled variable muffler. Lower engine vacuum indicates a higher rpm or engine load, which opens the muffler for a louder sound and less restriction.
Step Into Our Office
The inside of the Z06 and Z07 Corvettes aren’t much different from our standard Stingray Z51. Carbon fiber is more exposed on the more-capable cars, but you’ll also notice something about the tachometer: Rather than a 6,500-rpm redline when it reaches operating temperatures, the new LT6 allows you to rev as high as 9,000 rpm (!).
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