AUSTIN, Texas—By just my third lap in the top-spec 2025 Chevrolet Corvette ZR1, I glanced down at the speedometer toward the end of the Circuit of the Americas’ long back straight and spied 181 mph (291 km/h) displayed for a split second.
COTA reveals the ZR1’s excellent balance, especially when specced with the optional aero package, carbon fiber wheels, and Michelin’s Cup 2 R tires.
Biggest turbos ever The ZR1’s engine, dubbed LT7, shares much with the 5.5 L naturally aspirated LT6 engine in the less-powerful, cheaper Z06.
A track designed for corner exit speeds double my pace in the ZR1 helps explain why Chevrolet declined to set us loose on public roads behind the wheel.
We’ve probably reached peak internal-combustion Corvette, which is something of a hint about the all-too-real question of where Chevy can go from here.
AUSTIN, Texas—On my third lap in the top-spec 2025 Chevrolet Corvette ZR1, I caught a glimpse of 181 mph (291 km/h) briefly on the speedometer near the end of the Circuit of the Americas’ lengthy back straight. Given that the $174,995 ZR1’s twin-turbocharged V8 only delivers 1,064 horsepower to the back wheels, it’s not bad for Chevy’s newest flagship sports vehicle.
The ZR1 also captured your attention as it tackled the steep uphill toward the first corner and then wound through a series of difficult corners with plenty of elevation change. The US’s only purpose-built Formula One track was a great place to sample Corvette’s latest. Fortunately, Chevy brought a team of engineers to explain how the entire package works together to enable such an amazing pace and how the company can responsibly sell such a powerful car to the general public. The car itself is an engineering marvel.
Better weight distribution and the ability to compete against more exotic European OEMs like Ferrari were the main goals of the Corvette’s eighth generation switch to a mid-engine layout. Due to the suspension and tire orientation, the front-engined car’s engine bay was too narrow to accommodate two turbos. As a result, the final Corvette to be given the ZR1 badge had to use a supercharger to keep peak power at “just” 755 horsepower (563 kW).
When equipped with Michelin’s Cup 2 R tires, carbon fiber wheels, and the optional aero package, the ZR1’s exceptional balance is revealed by COTA. Improved lateral acceleration and reliable application of four-figure horsepower to the asphalt are both made possible by the tires, which are essentially grooved slicks. However, Chevrolet’s engineers readily acknowledged that the ZR1’s initial goal was only 850 horsepower (634 kW), until 1,000 became apparent and required significant ingenuity to consistently achieve.
largest turbos ever.
The LT7 engine in the ZR1 is very similar to the 5.5 L naturally aspirated LT6 engine in the less potent, less expensive Z06. Even though an LT6’s dry-sump oil tank may have allowed for the installation of turbos all along, the engine still has a flat-plane crank and dry-sump oiling.
Even with the throttle closed, the computer-controlled wastegate actuation maintains an anti-lag boost of 6 to 7 psi. The two 76-millimeter turbos, the largest ever installed on a production car, necessitated new intake routing. A mechanical system normally needs to maintain a 7 percent margin of error, but the ZR1’s is more like 2 to 3 percent. Turbo speed sensors enable the turbines to spin closer to maximum speed before the vanes physically break apart.
We’ve been informed that during early testing, the final power output actually broke two of Chevrolet’s dynos. The eight-speed dual-clutch transmission of the C8 therefore required strengthening with physically wider gears that were shot-peened for extra strength in addition to a new lubrication system. In contrast, the engine generates significant cooling demands when operating at full throttle, which is closely related to the downforce needed to reach such high speeds.
Because of this, the ZR1 forgoes its usable frunk in favor of a huge radiator, and the heat extractor on the hood also feeds trapped air over the roofline. This made more room for the front fascia to cool down, which is another advantage of canard spat dive planes. An extra inlet on the side strakes completes the incredibly broad scoops that were first seen on the Z06. Next, coupes get new shoulder NACA intakes that directly feed the air box with cooler oxygen, even producing a ram air effect similar to mild supercharging, and a split rear window that evokes vintage Corvettes while releasing hot air from the engine bay.
Because the LT6 and LT7 use incredibly tight tolerances between the crankshaft and connecting rods, which require that the 5W-50 oil be kept below 120° C (248° F) at all times, cooling for the ZR1 became even more important. Additionally, I only observed oil temperatures occasionally rising above 104° C (220° F), even on a hot and muggy Texas day, demonstrating how easily the system operates.
I skipped out while wearing a helmet because the hardtop convertible ZR1 has no shoulder intakes or split-engine venting, and it also drastically reduces headroom. Other reporters saw a decline in the convertibles’ performance, likely more pronounced than the slight weight increases of only roughly 100 pounds (45 kg) would indicate. In order to compensate for the Texas day, the ECU drew back timing and instead permitted a mild overboost of 24 to 25 psi, which is likely due to temperature. Nevertheless, an engineer acknowledged that he believed the engine was likely only 5–10% powered.
This Corvette sounds even more crazy given that I achieved my highest top speed ever, even though the ZR1 might have lost between 53 and 106 horsepower (40 and 80 kW). However, because the DCT’s gear ratios are carried over from the Stingray, I ended up driving the turbos because they depleted the power when I went from second to third and then third to fourth.
It seems to me that on a track this size, nothing less than an F1 racecar feels this fast. Chevrolet refused to allow us to drive on public roads because the track was built for corner exit speeds, which is twice as fast as my ZR1 speed.
However, that worries prospective purchasers, which is why the ZR1’s electronics surely temper the madness. Even if the ABS runs at 5 milliseconds and the ESC at 20 milliseconds, Chevy still uses Bosch’s ninth-generation traction control, which debuted on the C7 and runs on a 10-millisecond loop. I suspect that in addition to the torque-by-gear limitations in first and second that are intended to protect driveline components, this computerized nannying caused me to slow down quite a bit.
The Corvette’s internal combustion has likely peaked, which is a clue to the all-too-real question of where Chevy can go from here. If this is true, this vehicle achieves a new degree of unimaginable American ingenuity along with a newfound level of sophistication and traction control that makes an effort to minimize—if not completely eliminate—the unquestionable ridiculousness.
