DAYTONA BEACH, Fla. – Ilmor Engineering and NASCAR have announced the preliminary results of an investigation the engine failures during the recent NASCAR Gander Outdoors Truck Series race at Las Vegas Motor Speedway.

Four of Ilmor’s NT1 engines failed during the World of Westgate 200 on Sept. 13, including those in the ThorSport Racing Ford trucks of playoff drivers Grant Enfinger, Johnny Sauter and Matt Crafton. The engine in the Young’s Motorsports No. 02 of Tyler Dippel also failed.

As a result of the engine failures, Enfinger and Sauter both failed to advance to the second round of the Truck Series playoffs. Enfinger was the regular season Truck Series champion entering the playoffs.

Ilmor Engineering attributed the engine issues to, “the high engine load condition combined with the extreme weather conditions in Las Vegas,” according to a statement from company officials.

“Ilmor Engineering is committed to our partnership with NASCAR and to the long-term development of the NT1 engine,” the company said in its statement. “To that end, following the issues experienced by a number of different teams and competitors during the Sept. 13 race at Las Vegas Motor Speedway, engines were returned to the NASCAR R&D Center for technical inspection and data review. The combination of the high engine load condition combined with the extreme weather conditions in Las Vegas resulted in some engines suffering severe detonation. Ilmor is taking new measures in engine calibration to ensure to this situation is corrected for all future races.”

In a story appearing on NASCAR.com, it was revealed that NASCAR officials visited the ThorSport Racing shop in the days after the race at Las Vegas to collect all of the damaged engines. They also collected the engine from the No. 99 ThorSport truck driven by Ben Rhodes when it was discovered that engine also suffered some damage.

Additional issues were discovered in other NT1 engines, including the engine out of the No. 24 GMS Racing Chevrolet driven by Brett Moffitt, resulting in Ilmor requesting all 32 engines be returned to their shop for inspection.

According to Andrew Richards, a motorsports development engineer with Ilmor who was quoted in the NASCAR.com story, there was no particular part that resulted in the failure of the engines. Instead, failsafes in the engines turned out to be “insufficient.”

“We commend Ilmor Engineering for their thorough review and the forthright way they’ve claimed ownership of the engine issues suffered by teams during the Sept. 13 race at Las Vegas Motor Speedway,” NASCAR officials said in a statement. “The NT1 engine has played a vital role in the health of the NASCAR Gander Outdoors Truck Series and that’s been evident in the tremendous competition we’ve seen all season. We’re confident that will continue in the years ahead.”