With Chevrolet’s recent reveal of the incredible C8 ZR1, there seemed no better time to do a deep dive on one of the most powerful badges in the history of the autoverse.
The ZR1 or ZR-1 (depending on which generation is being discussed) was brought about as a no-frills, all-out race car for the street. Now in its fifth iteration with the new C8 variant, the first ZR1 appeared all the way back in 1970 as a C3 option package. This no-nonsense package defined what would become the most feared and revered Corvette trim in history.
What does ZR1 stand for?
Unlike today, the ZR1 was not marketed as a separate stand-alone showroom car. Much like the original Corvette Z06, the ZR1 was nothing more than an optional RPO code that could be checked off while purchasing your new 1970 Corvette.
Chevy has never offered an official statement as to what ZR1 actually stands for. Still, many Vette enthusiasts have speculated that the alphanumeric badge is short for “Zora Racer One” as a nod to the Corvette’s creator, Zora Arkus-Duntov. This seems plausible enough, and as fans ourselves, we’d like to believe it.
Although also never officially stated, the ZR1 has come to embody the true racing soul of the Corvette in its purest form, far beyond the typical muscle car mentality prevalent during the mid-1960s and early 1970s. Zora Arkus-Duntov wanted his masterpiece to be more than a musclebound drag racer. He wanted the Corvette, specifically the ZR1, to be a true lightweight track car capable of taking on anything from a Plymouth Superbird to a Shelby Cobra, regardless of whether the track was straight or curved.
What engine came in the original Corvette ZR1
While there was no shortage of massively powerful big block V-8s in Chevy’s parts bin to choose from during the tail end of the Golden Age of muscle cars, curiously, the ZR1 was optioned with a 350 cubic-inch LT-1. This, however, was no ordinary small block.
The 1970 LT-1 was an iron block topped with aluminum heads and an aluminum dual-plane intake manifold fed by a 780-cfm Holley carburetor. Forged pistons, a solid-lifter camshaft, and an incredibly high (for an NA engine in 1970) compression ratio of 11.0:1 all allowed the mouse motor to pump out a heroic 370 hp at 6,000 rpm and 380 lb-ft of torque at 4,000 rpm. With its staggering 1.1 horsepower per cubic-inch ratio, the LT-1 was easily the most potent engine in the GM lineup despite not being the absolute most powerful.
How much did an original C3 ZR1 cost?
Here’s the thing about prices from half a century ago: they all look ridiculously cheap. To better understand the true cost of something, we will look at what percentage of the base price each option would run its perspective owner, which would allow us to realize how expensive or not each item or package was.
In 1970, a base Corvette Sport Coupe ran you $5,192.00. Somewhat surprisingly, the base Corvette Convertible sold for a cheaper $4,449.00. However, for our purposes, we will use the Coupe as our basis for cost analysis.
The ZR1 RPO code box could be checked and had for $968.95. Once you get past the notion that you could have the purest, most race-ready C3 ever made for less than it would cost you to own a new C8 for one month (with insurance), that number equates to about 19% of the base price of a new Corvette in 1970.
Compare that figure with other options available to upgrade your C3, and it becomes clear that even back then, the ZR1 wasn’t a cheap option (relatively speaking). The LT1 engine could be added as a stand-alone option for $447.60 (about 9% of the base price), while the bigger and more powerful LS5 454 CID big-block set you back a mere $289.65 (5.5% of the base cost). 1970 saw 25 ZR1s built, while 1971 saw just 8 made, and in its final 1972 year, only 20 more ZR1s rolled off the assembly line for a total of 53 Zs in three years.
What made the ZR1 different than a base Corvette?
The ZR1 package was as hardcore as it could be had from the factory, and the truth is, it was just too much for many potential owners. Saying yes to the ZR1 meant saying no to anything and everything that might add time or weight to your copious track outings.
What the ZR1 package got you was its LT1 engine, a Muncie M22 close-ratio “Rock Crusher” heavy-duty four-speed manual transmission, heavy-duty power brakes, a specific lightweight aluminum radiator, metal fan shroud, and a beefed-up suspension that added firmer springs, shocks, and meatier stabilizer bars at both the front and rear.
Almost as important as what the ZR1 added is what it deleted. Checking the ZR1 box meant saying goodbye to creature comforts such as air-conditioning, power windows, power steering, an alarm system, window defroster, deluxe wheel covers, and an AM/FM stereo.
So, for someone just looking for a comfortable, good-looking Sunday driver, it becomes easy to see why their frugality and/or practicality might have allowed them to pass on the no-frills, no-nonsense ZR1 easily.
How many C3 Corvette ZR1s were made?
While just 53 of these diehard race cars for the road were produced in their debut to the car-buying world, the effect echoed for decades. Once the country got past the dark ages of horsepower-sucking emissions purgatory that marred the tail-end of the C3 generation, Corvette engineers decided it was time to resurrect its mightiest nameplate for the C4. Picking up where the C3Z left off, the fourth-gen version of the ZR1 catapulted the Corvette into nigh-supercar status.
