NMCA Dart NA 10.5 Presented by Diamond Pistons Driver David Theisen On Right Path After Tracking Down Trouble

By Mary Lendzion

Resolved and resolute in his approach to racing, David Theisen does whatever it takes to have a competitive car and combination in NMCA Dart NA 10.5 presented by Diamond Pistons.

As a result, he has wheeled to wins and captured a championship in the category in his 1969 Firebird powered by a naturally aspirated 611 cubic-inch Chevrolet built by Chris Uratchko of Uratchko Racing Engines, topped with Slick Rick Racing heads and a Marcella Manifold intake and backed by a Proformance Racing Transmissions’ Turbo 400 and two-piece Ultimate Converter concepts converter.

Committed to continuous improvement, the Michigan-based driver was making mild changes to his car’s combination in 2019, but they weren’t revealing the results that he had hoped they would.

“I was trying different things with the transmission gearing, rear-end gearing, the converter and the shocks to see if I could get the car to run better in the 60-foot, down low and on the bottom end of the track, and while what I was doing seemed to make sense, it wasn’t translating to the track,” said Theisen, whose car rolls on a ladderbar suspension set-up. “I was going in the wrong direction.”

As a result, Theisen couldn’t get his car to be consistent.

“I basically went through 2019 without discovering what I needed to discover,” said Theisen, who still pulled off a fourth-place finish in NMCA Dart NA 10.5 presented by Diamond Pistons points as well as a win in All Motor at Milan Dragway in Michigan.

After studying his data and giving it some serious thought over winter, he turned his focus to the first race on this year’s NMCA tour, the 18th Annual NMCA Muscle Car Mayhem presented by Holbrook Racing Engines in March at Bradenton Motorsports Park in Florida.

“I knew what I wanted to try at the event in Florida, but unfortunately, when I did, it didn’t help,” said Theisen. “My car was spinning on the starting line in qualifying, so, I started changing more stuff. We had a spare transmission with different gearing, so we put that in before the last round of qualifying, and my car should have gotten down track with that, but it didn’t.”

Though he turned in an off-pace 8.32 in qualifying, he wasn’t quick to quit.

“Another NA 10.5 racer, Joe Clemente, and his crew guys, were helping me figure it out, and they had a spare set of rear shocks, so we put them on my car, and it went straight down track,” said Theisen, who trapped a 7.84 to take the win in the first round of eliminations over John Langer, who was right there in the super-tight race with a 7.85, and had set the pace in qualifying and set class records earlier in the weekend with a 7.76 and 177 mph.

“So, in trying the spare rear shocks that Joe Clemente gave us, we think we found something,” said Theisen, who advanced to the final round of eliminations, where he was a wee bit quick on the shift into second gear, which scrubbed some of the car’s momentum, and he finished as the runner-up against Rich Nye.

“I feel a lot more confident now about the changes we had been making and the changes we’re going to make, and in the direction we’re going in, and I really want to thank Joe Clemente and his crew, as well as my crew, including my wife, Anna, my parents, Virginia and John, Kevin, Sean and Big Steve,” said Theisen. “Hopefully everything is coming together now. I need it to be, because the competition is incredibly tough in this category.”

There’s no doubt that Theisen, who’s currently holding down the second place in NMCA Dart NA 10.5 presented by Diamond Pistons points, will give it everything he has to hold onto it, or move up, at the Scoggin-Dickey Parts Center NMRA/NMCA Power Festival presented by HPJ Performance, May 28-31, at World Wide Technology Raceway in Madison, Illinois.