If you ticked a certain box in 1987, your brand-new car didn’t go straight to the dealer. It rolled off the line, got loaded onto a truck, and vanished for a few weeks. Somewhere far from the factory, a man with a mustache and a vision tore it apart, stuffed two turbos into it, and sent it back, still covered by the factory warranty.
That was the deal between General Motors and Reeves Callaway, the quiet engineer who convinced America’s biggest carmaker to hand over its flagship and let him make it faster.
Callaway wasn’t a marketing guy. He was a craftsman disguised as an engineer, a racer who understood the poetry of precision. In his small Connecticut workshop, he built turbo systems that turned European cars into perfectly mannered monsters. His BMWs, Alfas, and Volkswagens didn’t just go quicker; they went smoother. Power and polish in equal measure. It was enough to catch Detroit’s attention.
By the mid-1980s, Chevrolet needed an answer. The Corvette was competent, but not feared. Europe ruled the language of speed, and inside Chevrolet, the engineers were choked by paperwork and fear. The oil crises had beaten the fun out of the place. Risk was dead. Committees made decisions that engineers should have made. Callaway offered an escape route. He’d take their car, give it teeth, and send it back with manners. GM listened, and, against its own nature, said yes.
From 1987 to 1991, if you ordered RPO B2K, your new car left Bowling Green, got trucked to Old Lyme, and returned weeks later reborn. Callaway’s crew bolted on twin turbos, intercoolers, and a web of polished plumbing that somehow worked like it had been designed there from the start. It came back still under warranty, but now capable of shredding Europe’s elite.
“It’s a car that surprises you,” said owner Alex Leventhal. “It looks like a Corvette, but the way it builds power, it’s silk until it isn’t. You can tell it wasn’t designed by a committee.”
The standard Callaway Twin Turbo was quick, smooth, and deceptively civilized. But for the lunatics, there was the Wunderbar Option. “That’s where it crosses into madness,” Alex said. “The boost hits like a second engine waking up, and the car stays completely composed while everything else goes blurry.”
The Wunderbar cars were the high point. Tuned closer to 400 horsepower and 575 pound-feet of torque, they turned the polite Twin Turbo into something that could stalk the likes of the Ferrari F40 and Porsche 959. The comparison wasn’t hype. It was math. In an age when American performance was measured in quarter-miles, Callaway was speaking in top speed and sustained boost. The Wunderbar would cruise near 200 miles per hour on street tires, cold air blowing through the vents. It was absurd. A Corvette, a fiberglass car from Kentucky, hanging with Maranello’s best.
It shouldn’t have been possible. The F40 was sacred—a million-dollar altar to violence and ego. The Callaway was its antithesis, born of pragmatism and patience, and it could still catch it on the straights. That kind of heresy didn’t fit the narrative. Relatively speaking only a few Callaways were built, and while an F40 now trades for millions, a pristine Twin Turbo might fetch a few hundred thousand. Same era, same power, same speed, different mythologies. Europe had romance. America had results.
Early cars made 345 horsepower and 465 pound-feet of torque. The later Wunderbar-spec added bigger turbos, better intercooling, custom wastegate tuning, and fuel mapping that made the power come on like a tide instead of a punch. It changed the character without killing the charm. The real magic was how it behaved. It started clean, idled smooth, and handled traffic without complaint. It wasn’t brutal. It was balanced.
“When you drive it, you get what Callaway was chasing,” Alex said. “It’s calm until you ask for chaos, and when it comes, it’s perfect. It feels like something built by a person who cared.”
Other tuners went loud. Hennessey chased numbers. Lingenfelter chased trophies. AMG went corporate. Callaway went quiet, and his cars were faster for it. He was the outsider who made it inside and somehow stayed himself.
When GM bought Lotus and birthed the ZR-1, the partnership ended. The moment passed. But what it represented hasn’t. It was the last time a major manufacturer handed its flagship to a man and said, “Show us what’s possible.”
For Alex, that’s the whole reason his car matters. “It’s proof,” he said. “Proof that an American could match the best in the world, and that one guy with conviction could make the biggest company on earth believe in him.”
He looked at the car sitting in the sun, the turbos cooling under the hood. “Driving it now feels like holding a piece of American audacity in your hands,” he said. “It’s a reminder of when courage could still fit inside a workshop.”
Reeves Callaway died in 2023. But his cars still breathe. They’re more than fast—they’re evidence that craft once outran convention, and that sometimes, the smartest thing a corporation can do is trust the guy with the mustache and the crazy idea.
