The powerplant behind them was the legendary 427 “L88”, a 450-horsepower 7-liter engine found in many other GM cars including the Corvette. But this version had high compression, required race fuel, and made an insane-for-the-time 450 horsepower.
Check out this article where the Hot Rod staff weathers a ZZ427 to look like a 40-years-used L88. And if you have 12 minutes, let Tim Allen and Jay Leno walk you through the best of both worlds: a 1968 Camaro COPO clone with a modern 427 at its heart.
This has been but a taste of the vast GM Performance Catalog. GM crate engines run the gamut from affordable and economical four-cylinder mills to gallon-per-mile big blocks that sound like the devil gargling Listerine. And the future is bright: Chevrolet is bringing back the COPO Camaro and the newly-launched 2019 ZR1 packs 755 horsepower and a 210-mph top speed.
That didn’t stop this shop from stuffing the lower-compression street version into a 2012 GMC Sierra single cab truck, a vehicle which, as you may know, has almost no weight over the rear wheels. That must be a hoot to drive.