Corvette ZR1

1970-72 Corvette ZR1

The ZR1 name first appeared without a hyphen during the 1970 model year, when it was a performance package for the C3 Corvette.

The third-generation Corvette ZR1 was first introduced in 1970 as the successor to the L88 Corvette. The car, which could be ordered as Regular Production Option (RPO) ZR1, came equipped with a new, solid-lifter, small-block engine that GM designated the LT1. The LT1 engine, which was manufactured by GM from 1970–1972, was a 350 cubic-inch small block that produced 370 horsepower. It featured 11:1 compression, a ‘178’ high-performance camshaft and a 780 CFM Holley four-barrel carburetor mounted to a special aluminum intake. Although not as powerful as the L88, the LT1 engine offered consumers an exciting engine platform that could power their Corvettes at and around the racetrack.

In addition to the LT1 engine, Corvettes ordered with RPO ZR1 came equipped with the M22 “Rockcrusher” transmission, heavy-duty power brakes with dual-pin front brake calipers (J56), a transistor ignition, a special aluminum radiator and a heavier-duty suspension package that included bolstered 7-leaf rear springs, shocks and heavy-duty 5/8 inch front sway bars and rear spindle struts/stabilizer bars. The car also came equipped with metal fan shrouds. Moreover, when ordering a ZR1, the following options were deleted from the Corvette, including: a rear window defroster (C50), air-conditioning (C60), power steering (N40), deluxe wheel covers (P02), the alarm system (UA6), AM/FM radio (U69) and AM/FM Radio, stereo (U79).

The deletion of these items was intentionally designed to help reduce the car’s overall weight as well as to reduce the power load put on the engine, thereby ensuring that more power was transferred from the engine, through the transmission and to the rear wheels. In fact, it was impossible to order the ZR1 with any of the “creature comforts” synonymous with the more conventional Corvettes being offered by Chevrolet dealers across the nation. Despite this, the 1970 Corvette ZR1 could be ordered as a convertible!

The C4 Corvette ZR-1

The next ZR-1 came in 1990, adding the hyphen and an array of features that made this C4 very different from the others. The most significant difference was the Lotus-engineered 5.7-liter dual overhead camshaft V8.

The C4 ZR-1 Corvette, even some 30 years after its initial year of production, carries indisputable performance merit, the likes of which few can deny. In fact, the ZR-1 is often cited as the car which helped fend off threats, both foreign and domestic in origin, to the Corvette’s elite performance car status. However, after only 6,939 ZR-1 Corvettes were built, and 6 years of production had passed, the program was terminated, falling victim to corporate decisions regarding pricing and the mirror-like restyling of base model Corvettes of the era. While the ZR-1 was somewhat unceremoniously pulled from production, these robust racers are still renowned today for their brutish power and exemplary engineering.

The ZR-1 became available to the public in 1990. Aside from its obvious differences under the hood, the ZR-1 featured several cosmetic variances over its base model counterpart. Some of the most notable included a convex tail, signature square taillights, and special ZR-1 badging below the right rear light. The ZR-1 also featured 11” wide rear tires fitted on 17” rims. In the realm of performance, the ZR-1 matched or exceeded the expectations of most. The LT5 engine at the heart of the ZR-1 relied upon 32 valves (4 per cylinder), four overhead camshafts, and an 11:1 compression ratio to churn out 375 bhp. The ZR-1 was capable of 4.3 second 0-60 MPH pulls, and could cover ¼ mile in a mere 13 seconds.

The ZR-1 received high-praise from critics and Corvette enthusiasts alike, and yet a mix of questionable corporate decisions and instances of less than ideal timing ultimately doomed the ZR-1.

The C6 Corvette ZR1

The ZR1 returned again during the C6 era, once again without the hyphen, but it packed all sorts of power. The supercharged LS9 V9 delivered 638 horsepower and 604 lb-ft of torque, making it the most powerful Corvette to date.

Many of the body panels were comprised of carbon fiber to reduce weight while magnetic suspension, Brembo carbon-ceramic brakes, and huge, sticky tires came together to make this one of the best performing American cars ever. This machine could dash to 60 in just 3.3 seconds, running the quarter-mile with an 11.2 at 130.5 miles per hour and stop from 60 in just 97 feet.

The C7 ZR1 was the fastest production Corvette ever to that date and, moreover, was the quickest car in its price range. While the ZR lettering dated back to the '70s, it was the '90s model that stirred more emotions. The C7 ZR1 was the true King of the Hill among its brothers, and it was quicker than the much-famed Ferrari F430 from the same era. While it wasn't the best car on cornering, it was a hard-to-catch one on the drag-strip or in straight-line acceleration.

The Corvette followed the same principles as before: light, aerodynamic bodywork, and functional scoops on the sides. At the front of the car, a nose-scoop allowed more air to get to the supercharger covered by a transparent polycarbonate window area on the hood. It was the most extravagant idea made by GM designers for the beloved American supercar. In the coupe shape, the carbon-fiber roof featured two outgrows for the driver and the passenger.

Inside, the Corvette featured a modern-looking interior with an integrated infotainment system installed on the wide center stack. The tall center console hosted the short gear-stick, the handbrake, and a storage compartment big enough for a quick trip to the race-track. Its high-bolstered sport seats offered great lateral support. From the technical point of view, the ZR1 was more than just a Corvette with a more powerful engine. Its reinforced rear axle, the magnetic ride control, and the limited-slip differential were part of the package. A state-of-the-art fuel injection system fueled the supercharged 6.2-liter V8 engine, and the six-speed manual was the only option.

The C7 Corvette ZR1

Introduced for the 2019 model year and it was offered only for that year, the C7 ZR1 is the most powerful Corvette and the most powerful Chevrolet road car ever, with 755 hp and 715 lb-ft from the LT5. 

The C7 ZR1 was the most powerful Corvette ever made to that date and also the most technologically advanced. Corvette had a long history behind it. Even though its first generation was not the most powerful car on the market, its successors started to grow and develop more power and torque. They became more and more athletic and sportier. The C7 ZR1 model was also the last Corvette with the engine mounted in the front. It might be called the last classic ZR1 model.

Unlike its siblings, the ZR1 was easy to spot due to its hole in the hood and the carbon-fiber case for the supercharger. The engine was so tall that it couldn't fit in the engine bay, so the designers made a cut and passed it through. If the track-package was installed, the car featured various carbon-fiber elements at the front and on the sides, plus a massive wing on the back. It was mounted on the rear panel, not on the trunk-lid. Its light-alloy wheels were unique for the ZR1, with 19" at the front and 20" for the rear axle.

Inside, Chevrolet tried to make things better than before. There was no cheap plastic anymore. Depending on the options, the ZR1 could have been fitted with Alcantara on the ceiling. Its regular sport-bucket seats could have been replaced with the race-bucket ones, which featured integrated headrests and passages for a four-point harness.

The C7 ZR1 featured an adaptive dampers system with magnetorheological shocks. The electronically controlled Limited Slip Differential helped the car corner faster than any other Corvette in history. Its 6.2-liter supercharged engine produced a massive 765 hp and 969 Nm (715 lb-ft) of torque, which were sent to the rear wheels via a 7-speed manual or an 8-speed automatic gearbox.