Every Generation Of Corvette ZR1 Engines, Ranked By Max Horsepower

One of the longest-running and most successful sports cars of all time, the Chevrolet Corvette has a history of offering big performance numbers and a competitive edge over more expensive rivals. For a long time, the Corvette offered front-engine, rear-drive thrills, and eventually, the mid-engine eighth-generation Corvette arrived, providing even more of a performance boost.

Throughout every generation of the Corvette, the biggest achievements have always been ushered in by  high-performance trims like the Z06 and ZR1 models. Five different generations of Corvette have been graced with the ZR1 badge, dating back to the early. Now, with the 2025 Corvette ZR1 on the horizon, the cars are more powerful than ever before. 

The upcoming ZR1 model offers more than double the horsepower of a standard Vette, along with all sorts of performance upgrades and aesthetic differences. So what road did we take to get here? Where was power added along the way? An which ZR1 is the most powerful? Lets take a look at every Corvette ZR1 generation, ranked by horsepower.

Before it was a tire-shredding supercar with four-digit horsepower numbers, the Corvette ZR1 was just another RPO (regular production option) package. It was an option you could add to standard Corvettes if you checked the right box on the order form. The first ZR1 was an add-on for the third-generation Corvette (C3), featuring the same 350-cubic-inch (5.7-liter) V8 that other trim levels used. However, it had a number of features that helped it go faster like better cooling, superior suspension tuning, and upgraded brakes. The ZR1 also removed a number of creature comforts in the name of weight reduction. It had manual windows instead of power-operated ones, no power steering, no air conditioning, and no radio.

The C3 ZR1's engine, called the LT1, produced 370 hp and 380 lb-ft of torque. It was paired with a Muncie M22 four-speed manual transmission called the rock crusher. It's the least powerful ZR1 ever, but it's still extremely special amongst even the rarest Corvettes, with fewer than 60 models made between 1970 and 1972. Chevy also offered the C3 Corvette with an ultra-rare ZR2 package, which had similar performance upgrades, but with a massive 454-cubic-inch LS6 big-block. The ZR2 was only available in 1971, and its engine put out an impressive 425 hp, but it doesn't technically qualify as a ZR1.

It was nearly 20 years between the first ZR1 and its successor — a pumped up version of the fourth-generation Corvette. The Corvette C4 ZR-1, which notably was the only ZR1 with a dash in its name, hit the market in 1990. It had just a smidge more power than the C3 ZR1, but much more than the standard C4 Vette. The C4 ZR-1 was powered by a 5.7-liter V8, known as the LT5, that produced 375 hp and 375 lb-ft of torque. It was paired with a six-speed manual transmission –- not much of a leap by C3 ZR1 standards, but a significant increase over the standard 1990 Corvette, which only provided about 250 hp.

The LT5 engine was designed by Lotus, then built by Mercury Marine –- a specialist in boat engines. The LT5 was bumped up to 405 hp by the end of its run with the C4 ZR1, and it still holds the distinction of being the last naturally aspirated engine to power a ZR1 model. At the peak of its powers, when the LT5 was making 405 horses under the hood in the mid-'90s, it blasted the Vette from zero to 60 mph in 4.7 seconds.

The ZR1 has skipped a number of years throughout the Corvette's history, and sometimes, it skips an entire generation. That's the case with the third ZR1, which skipped the fifth-generation Corvette (1997-2004). The nameplate didn't show back up until the years of the C6 Corvette. 

With no C5 ZR1, and with the last C4 ZR1 being produced in the mid-'90s, that left a big gap. The C6 ZR1 finally arrived in 2009 – a supercharged beast that brought forced-induction to the ZR1 lineup for the first time, and with it, big power numbers.

The C6 Corvette ZR1 was powered by a 6.2-liter LS9 V8. It was fitted with an Eaton supercharger (that you could see through a lovely little window on the hood) and produced 638 hp and 604 lb-ft of torque. With the big, powerful, supercharged V8 under the hood, the C6 ZR1 was capable of achieving speeds in excess of 200 miles per hour, and it rocketed from zero to 60 mph in just 3.4 seconds. The C6 ZR1 lasted until 2013, just before the switch over to the seventh-generation Corvette, which would bring with it some pretty impressive stats of its own.

The title of most-powerful front-engine Corvette ever goes to the C7 ZR1. The last of the front-engine Corvettes and the last with a manual transmission, the C7 went out with a bang. Like the ultra-rare ZR2 from the Corvette's earlier days, the C7 ZR1 was only produced for one year (2019), and it had some pretty astonishing power figures. Under the hood, the C7 ZR1 got a 6.2-liter V8, much like the C6 ZR1 that preceded it, but this supercharged LT5 V8 made a lot more power. How much? Try 755 hp and 715 lb-ft of torque — huge leaps over the previous generation.

With that much power on tap, the C7 ZR1 was capable of some pretty impressive feats of acceleration, going from zero to 60 mph in just 3.0 seconds flat and handling the quarter-mile in just 10.8 seconds. Chevy claimed that the ZR1 was capable of achieving a top speed of 212 miles per hour. It was a fitting tribute to all the high-performance front-engine Corvettes that came before it, and an argument can still be made that the C7 is one of the coolest Corvettes ever.

There are a lot of superlatives worth noting when it comes to the eighth-generation Corvette ZR1. It's the first-ever Corvette to come from the factory with twin turbochargers, it provides 1,200 pounds of downforce (the most ever from a Corvette) at top speed, and it's the most powerful V8 produced by an American automaker. That leaves us with a Corvette that pumps out 1,064 hp and takes the top spot on our list of the most powerful ZR1s ever. The twin-turbocharged C8 ZR1 makes its peak power at 7,000 rpm and pumps out 828 lb-ft of torque at 6,000 rpm. Chevy estimates that the C8 ZR1 will break the 10-second barrier in the quarter mile. Zero to 60 mph estimates aren't in yet, but comparing the ZR1 to its Z06 brother could be helpful there.

The C8 Z06, powered by a 5.5-liter flat-plane-crank V8, produces 670 horsepower. In Car and Driver testing, the Z06 went from zero to 60 mph in just 2.6 seconds. By comparison, the ZR1 has 1,064 horsepower -– nearly 400 more than the current Z06 -– so, clearly, we expect it to be significantly quicker once production models are available for testing. Limiting factors like tires and available grip from the rear-wheel-drive layout may keep the C8 ZR1 from reaching 60 mph in under 2 seconds, but it will certainly inch closer to that incredible milestone.