Bryce Ronsonet took an interesting approach to building his off-road desert racer. Rather than starting with a truck or some other body-on-frame behemoth, the California native opted for a stock 1982 Mercedes 300SD as his blank canvas. After a bevy of modifications—which included using a reciprocating saw to alter the bodywork and routing its exhaust through the hood—Ronsonet entered his oil-burning beaut in the Mint 400, America’s oldest off-road race.

This is certainly not what the stuffed shirts in Stuttgart had in mind for the stately sedan when it rolled off the assembly line over 30 years ago. On the other hand, we’re betting you can’t find anyone having as much fun in their W123 as Ronsonet, who recently navigated 94 miles of Nevada’s trickiest desert terrain in his big Benz.

There was some damage on the front of the car that lowered its sale price. Ronsonet simply bent back the damaged metal and went about his business. A reciprocating saw also removed some of the wrinkled sheet metal while making way for larger tires.

It all started on the grid at the Mint 400’s Limited Race, on Friday. The cars and trucks on the race grid varied wildly. Rival rigs in Ronsonet’s Gambler class were all over the map, from a Subaru Justy to a four-wheel-drive limousine. Once we spotted the diesel Mercedes, though, we knew that we needed to find the mad scientist responsible for the crusty country clubber on stilts.

We first asked, “Why?” Ronsonet was quick with an answer.

“It was the cheapest thing we could find.”

Of course, off-road racing (like all forms of racing) can be an expensive endeavor. Side-by-sides offer higher speeds and lots of suspension travel, but they can be a rather pricey entry point. Many of the UTVs that were competing in Friday’s race cost more than $20,000. Stock!

Ronsonet’s build was bare bones, compared to many of the overbuilt dirt racers, but he spent the money where it would do the most good. “We’ve really only put a cage in it, lifted it, and slapped some nitrogen bump stops on it,” he said.

Then, there’s the engine. The stock 3.0-liter five-cylinder was rated at just 119 horsepower, which wasn’t going to be too exciting to bound across the desert. “We have a bigger pump on it and a bigger turbo on it, but it’s still the stock block,” Ronsonet said. There’s also a new air-to-air charge cooler to keep the temps down, but most of what’s under the hood is factory, even the head bolts are stock. The engine has been holding up well to 25 pounds of boost and is now churning out around 300 hp. The factory 722.3 four-speed automatic hasn’t complained, but its load was lessened when Ronsonet swapped in 3.92:1 gears from a four-cylinder model.

The HX30 turbo needed a spacer and some TIG welding to mount to the Mercedes five-cylinder. Before the lift, extra power, and larger tires, Ronsonet was seeing around 30 mpg. Now it’s about half that. Still, plenty of Mint 400 competitors would kill for that kind of fuel economy.

 

Those shorter gears help make up for the 31-inch BF Goodrich Mud Terrain KM3 tires that soak up the punishing desert floor. And about nine inches of wheel travel help to usher the rig over obstacles. Ronsonet fabbed a simple suspension that uses Ford Super Duty coils in the rear, twist-in spring spacers in the front, and off-the-shelf Bilstein shocks and nitrogen bump stops on all four corners. “For big whoops, we have to go pretty slow, but on rough roads it’s great,” he added.

As for the budget, Ronsonet kept a basic tally. “With the cage and everything, we’re probably right over $20,000,” he said. The cage was about half of his budget. It cage runs along the bottom of the body and ties into a substantial skidplate. Adding safety and durability to the old sedan—that’s money well spent.

The goals for this Mint 400 were simple, and Ronsonet summed them up in one word: “Finish.”

He eventually elaborated, stating that he would also like to hit 80 miles-per-hour across the dry lake bed—the smoothest, fastest part of the race course. We’re happy to report that the smoke-belching golden Benz met both goals, hitting 99.8 miles-per-hour on the bed en route to a second-place finish in its class. The duo’s next stop is the 500-mile Vegas to Reno race, for the Best in the Desert series.

We asked Ronsonet if he’d recommend others who are looking to build an affordable off-roader to take a similar route. “It’s very hard to find parts where I am … but if you can find parts for these cars, oh yeah. If you can find them cheap enough, absolutely!” If you’re inspired to prowl Craigslist for one of these five-cylinder bargains, we’re sure that Ronsonet and the rest of his desert racing competitors will welcome you to the grid.

Just don’t tell the side-by-side drivers about the screaming deal that you got on your desert racer.