A 1983 Mazda GLC Race Car From the Glory Days of IMSA

Last of Its Kind

A total of 12 factory-backed cars were built, but Geoff has talked to all their previous owners and confirmed: His is one of two that still exist, and the only one running. Though the series was ostensibly designed for lightly modified street cars, this GLC saw some pretty serious work.

The Koteles car shifted the engine down 1.5 inches and back almost 3 inches to improve weight distribution. This also got the axles lined up more directly with the hubs. Moving the engine wasn’t technically allowed, but they did a good job making it look factory. The tech inspectors never noticed. 

Mazda geeks peeking under the rear suspension will see a very familiar setup on this BD-chassis car. The rear strut uses two transverse links and one trailing link, a setup very similar to what you’d see under Protegés and Ford Escorts for decades to come. 

Photography Credit: Alan Cesar

Geoff’s car, though, looks almost factory fresh. It doesn’t show the wear, rust and neglect you’d expect to find on a forgotten, decades-old race car. Coil-over suspension graces all four corners. As part of the race build, the rear strut towers were completely remade and integrated with the roll cage. 

Unfortunately, the car was never very competitive. “It floundered,” Geoff says, citing that Mazda took the car to display at the four major auto shows right after it was built. “We didn’t get a lot of development time. We blew the first two motors and two transmissions. Once we got it sorted for the second season, things went much better and we were finishing in the top 10. But then IMSA started changing the series. They let the Dodge Chargers in, with 2.2-liter de-turboed engines. They made so much more power.

“We kept making more and more horsepower but kept blowing gearboxes, so Mazda had 12 custom, dog-ring racing gearboxes built. They were works of art. It looked like a mini Hewland: bronze shift forks, hardened shafts, straight-cut gears, Quaife limited-slip, all custom-machined.

There are two still in existence. That transmission is the only thing left that can handle this power.”

Despite the car’s technical bright spots, Geoff and his father ended its career soon after it began. It went into hibernation for 30 years, and the Mazda 626 became the next car to chase the Chargers.

Sourcing Unique Internals

Mazda became the featured marque at the 2013 Classic Motorsports Mitty, and the company asked Geoff to stir the car from its slumber for that vintage racing festival at Road Atlanta. He then took it through driving school as it was, with an engine that had been broken in but never raced. It lasted until the final session of the weekend before it threw a rod through its 1.5-liter block. “Back in the day, the rod bolts they used were cheesy. You can see where it sheared,” he says.

Geoff then began his two-year process of rebuilding an engine made of unobtainium. “I had a billet crank made for it by a guy who makes cranks for NASCAR. He knife-edged the leading side, bullet-edged the trailing side. There are no holes for balancing; it’s done completely by grinding. Arias pistons, Carillo rods, Ferrea stainless valves: There’s not one part you can get off the shelf. Every part involves calling across the country,” Geoff sighs. It’s the only part of the build that frustrates him.

Photography Credit: Alan Cesar

That work nets impressive horsepower. The dyno showed 190 at the wheels, but to call it peaky is an understatement. “It loves to go to 8500 rpm. That’s its sweet spot. It’ll go to 9000, but I’m not gonna push it that hard. Below 5000 it falls on its face, but once you hit that, it’s like a nitrous button,” Geoff says.

He rediscovered the stock transmission’s weakness firsthand at the 2013 Classic Motorsports Mitty, his third event since reviving the car. “I couldn’t afford the parts to put that racing box back together [at the time],” he concedes. “It needed some work, and getting the parts meant I had to find someone who could remanufacture them for me at a reasonable cost.”

Running a weaker trans was a gamble, and he lost. The gearbox failed during a test session. Geoff took it in stride–he expects failures as part of what it’s like to go racing. 

His wife, Beth, wasn’t as stoic about the breakdown. She fought back tears as she explained seeing her husband toil passionately on this project. Springtime is his busiest season at work, when he pulls 50- and 60-hour workweeks. Getting the car ready for the Mitty added 12-hour workdays on weekends. 

Beth came with him to the race, carrying food and providing trackside help. She helped push the car into place for our photo shoot. “I support him as much as I can, in a heartbeat. I see how hard he works. But then he drives the track, and boom,” Beth says as she wipes her eyes.

Savannah Success

Geoff did eventually get the racing gearbox ready to go, though. He freshened the car in time for the Savannah Speed Classics event at Hilton Head, where he completed every race without incident.

Finally, the car’s holding together. It’s developed enough that Geoff doesn’t have to work on it every weekend. He can now relax and enjoy the race. Look for him at HSR races, honoring his family and his personal history with the car’s original Beck’s Beer livery.

Photography Credit: Alan Cesar