With a cool head and competitive spirit, David Theisen has achieved a lot of success in racing over the years.
He earned the NMCA Dart NA 10.5 championship in 2018, and more recently, he pulled off a third-place finish in Small Tire Pro Stock and a second-place finish in All Motor at Darana Dragway in Michigan in 2025.
The Michigan-based racer who famously flies banners for sponsor LaFontaine Performance Center, ran as quick and fast as 7.70 and 178 mph in his fan-favorite Firebird powered by a 500 cubic-inch DRCE engine by Uratchko Racing Engines and a Turbo 400 by Proformance Racing Transmissions last year, and he is now preparing to put down even more power.
Chris Uratchko of Uratchko Racing Engines is going over Theisen’s engine before he gives it the go-ahead, and this year, rather than the automatic transmission Theisen has relied on for years, his engine will be paired with a five-speed from Liberty’s and a Ram billet clutch.
“I was fast with the automatic transmission, and I was happy to take it as far as we took it, but I decided toward the end of last year that I wanted to try something new with a five-speed transmission,” said Theisen, who runs a Holley Dominator system. “Jim Filipowski and Travis Gates did the switchover, and they knocked it out really fast. They had a lot of work to do in the transmission tunnel area, and they did some bars in the car along with some wiring related to the transmission, and we set up the clutch pedal.”

Small Tire Pro Stock racers Dwight Ausmus and John Langer stepped up with several suggestions for Theisen, to ensure their fellow racer had even more success with his new five-speed set-up.
Theisen hopes to get dialed-in with a test session or two before heading to the Small Tire Pro Stock race set for May 22-23 at World Wide Technology Raceway in Illinois, as part of Nostalgia Drag Racing League Route 66 Rockabilly Reunion. He will continue his Small Tire Pro Stock championship chase on July 10-11 at Lucas Oil Indianapolis Raceway Park in Indiana, as part of Nostalgia Drag Racing League Hot Rod Nationals presented by Ray Skillman Automotive Group; August 8-9 at Lucas Oil Indianapolis Raceway Park, as part of Lucas Oil Drag Racing Series NHRA North Central Division 3 Divisional Race; September 11-12 at Darana Raceway in Ohio, as part of Nostalgia Drag Racing League World Nostalgia Drags and October 23-25 at Lucas Oil Indianapolis Raceway Park, as part of NHRA North Central Divisional Division 3 Fall Classic.
“My wife, Anna, does not know this part yet, but she is going to learn how to do maintenance on a clutch,” said Theisen, with a laugh. “I am excited to see how it goes, and hopefully I won’t suck. I think I will have more tunability, especially down low on hot days, and I think the car will pick up through the top end of the track.”

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