MARENGO – Nick Priegnitz admittedly felt more anxious than ever in the days before he and his other employees left their diesel truck shop in Marengo for a one-mile track in Beeville, Texas.

A prominent speed competition, the Texas Mile in Beeville typically draws motorists throughout North America eager to test the performance and speed of their sport cars, like Corvettes and Lamborghinis, along a one-mile stretch of airport runway.

But for Priegnitz, the Texas Mile represented an opportunity to show outsiders Duramax Tuner, a brand of his company Calibrated Power Solutions that modifies and calibrates diesel engines and transmissions.

Diesel pickup trucks at the Texas Mile usually haul the sport cars onto the track, said Priegnitz, a Crystal Lake native. When they arrived at the track earlier this spring, Priegnitz and his employees rolled out a heavily modified 2001 Chevy Silverado, originally designed to top 98 mph.

Their intention was to run the truck and beat the fastest diesel pickup record – 167 mph – set at the Texas Mile. The anxiousness that had been building followed Priegnitz to Beeville.

“I wouldn’t say I was confident. I knew we had a good chance to do well, but hurdles are everywhere,” he said. “We were a long way from home.”

A chance opportunity led the company to the Texas Mile, after one of its vendors dropped out and offered the company a spot.

Three employees logged daylong hours for 10 days to modify the diesel truck, but a short deadline meant they couldn’t test the modifications until their first pass on the Texas Mile.

To compete for the diesel record, the company needed to triple the truck’s horsepower.

“We are looking at more than triple the horsepower without any additional cooling capacity, space or weight,” Priegnitz said. “Our main challenge was making that power and keeping that truck cool. That’s the only way it stays alive.”

At Beeville, the company unveiled a truck modified with compound turbos, dual fuel pumps, an altered transmission and an ice-water intercooler system meant to prevent the engine from overheating.

Driver Owen Powell, a Harvard resident and lead diesel tech at Duramax Tuner, hadn't operated a diesel truck faster than 135 mph. Without testing the truck, Powell said his legs were shaking moments before the first pass at the Texas Mile.

He ended it satisfied after the truck ran straight without reaching the record speed of 167 mph. On another pass, Powell eclipsed the fastest diesel pickup record, reaching 169 mph.

After Priegnitz analyzed performance data from the pass, he was assured the modified truck could potentially reach 174 mph before breaking down.

Powell later reached 172.2 mph with the modified Silverado, beating the original diesel record by roughly 5 mph.

“It was a good feeling at the end of the day that we got what we wanted to accomplish, and that the truck was still in one piece,” Powell said.

Priegnitz had a similar takeaway from the Texas Mile. The company, he said, successfully showed people at the event how it applies innovative approaches to engine tuning.

The event marked years of development for Priegnitz. He started the business as “a pet project” in a garage at Rochester, Minnesota, while he studied for his master’s in business at the University of Minnesota in 2007.

Years after graduating from Crystal Lake Central High School, Priegnitz returned home to further the business, later moving to a store in Union. He moved the company to Marengo last year, occupying a 16,000-square-foot office and garage.

The company now fields requests from diesel pickup drivers across the country who use Duramax and Cummins platforms and want performance modifications to their vehicles.

“A big part of making that truck live at the Texas Mile was achieved through our engine and transmission calibrations – the way we tune the truck,” Priegnitz said. “Going fast is not difficult. Going fast and coming home in one piece is difficult.”