No Radio Allowed: Inside the Original Corvette ZR1

Twenty-five people checked the ZR1 box on a 1970 Corvette order form. Chevrolet gave the option a dry name, the “Special Purpose Engine Package,” and priced it at $968.95. For that money, a buyer got race-tested parts built around a new solid-lifter small-block, plus a list of comforts the factory refused to install.

More than five decades later, ZR1 is the badge on the most powerful Corvettes Chevrolet sells. The C8 ZR1 uses a 5.5-liter twin-turbo LT7 rated at 1,064 hp, and the all-wheel-drive ZR1X adds a front electric motor for 1,250 hp combined. The original 1970-72 package lasted three model years and 53 cars, so it rarely comes up when people talk about Corvette history. It deserves more attention than that. The first ZR1 was Chevrolet’s last factory road racing package of the solid-lifter era, and it arrived just as new emissions rules began to change the car.

How the ZR1 Ended Up in the 1970 Order Guide

The 1970 Corvette got off to a slow start. A strike in 1969 led GM to keep building 1969 models for about two extra months, and the shortened 1970 run ended at 17,316 cars, the lowest total of any C3 model year. Under the hood, the lineup had changed too. Chevrolet retired the 427 big-block and the race-oriented L88 after 1969 and introduced a 454 along with a new small-block called the LT-1.

Auction houses often call the LT-1 Zora Arkus-Duntov’s pet project. Duntov, the Corvette’s chief engineer, had pushed for factory racing parts for years, and the LT-1 gave him a high-revving small-block with solid lifters and 370 hp. On its own, the engine cost $447.60, and 1,287 buyers added it to their 1970 cars. A much smaller group wanted the complete racing setup, and for them Chevrolet offered RPO ZR1, which collectors usually describe as the L88’s successor. Richard Prince of Corvette Magazine wrote that the primary purpose of these cars was road racing, and the parts list makes that hard to argue with.