After making its return to the 24 Hours Of Le Mans last year, the Viper GTS-R race car won’t be among the lineup at this year’s race. The information was revealed by SRT boss Ralph Gilles, though he is yet to give a reason for the decision.

“We regretfully and respectfully decline to participate in this year’s 24 Hours of Le Mans,” Gilles told Autoweek. “We are honored to once again be invited by the [race organizer, the Automobile Club de l’Ouest] to compete in this historic event, and they were the first to be informed of our decision. We will remain focused on our North American racing program in 2014.”

A possible issue is the cost of competing in the TUDOR United SportsCar Championship, which has more races than the standalone American Le Mans Series. SRT is thought to be focusing on American events in order to lure potential buyers and turn around flagging sales. It’s also thought that SRT is focusing on its privateer Viper GT3-R race car designed for the United SportsCar Championship’s GT-Daytona class.

For three consecutive years, from 1998 through 2000, Vipers took both first and second place in the GTS class at the 24 Hours of Le Mans. Last year, SRT entered two examples of the latest Viper in the equivalent GTE Pro class and managed to come a respectable 24th overall. Porsche won the class, with one of its 911 RSRs coming 15th overall.

The ACO will reveal in the coming weeks the two cars that will replace the Vipers in this year’s 24 Hours of Le Mans, which takes place in June. The good news is that ACO officials are said to be confident SRT will be back in 2015’s race.

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