The president of Toyota Racing Development says the engine failures incurred by the three Roush Fenway Racing teams during Sunday’s Sprint Cup race at Las Vegas Motor Speedway were unrelated to the problems five Toyota teams experienced on Saturday.

“Not in any way related,” Lee White said on Monday. “We’re going to take 100 percent responsibility for maybe not having all of our ducks in a row with durability testing when we got to the racetrack to be ready for the decisions the teams put the engines through to get ready for qualifying.”

Four teams supplied engines by TRD — David Reutimann and Marcos Ambrose of Michael Waltrip Racing and Brian Vickers and Scott Speed of Red Bull Racing — had to switch engines and start at the rear of the field.

Pole-sitter and eventual race winner Kyle Busch also started at the back of the field after switching engines, but his was built by Joe Gibbs Racing.

White said all seven teams supplied engines by TRD likely will go to Atlanta this week with the same new generation engine but with the conservative package — a thicker lubricant and small mechanical change that determines how much oil stays around the camshaft — that reduced horsepower by three to four at Vegas.

He blamed the Toyota failures on teams trying to get more horsepower out of the engine for qualifying and practice. Instead of returning to Charlotte, N.C., on Monday he flew to TRD headquarters in California to make sure the issue wasn’t a factor moving forward.

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