Alexander Sims and Rob Bell have become McLaren works driver and will race the constructor's MP4-12C GT3 car in international events this year.
Sims is putting his open-wheel career on hold to compete in GTs, having raced in the F3 Euro Series and GP3 over the past couple of seasons.
He will be placed with one or more of its customer teams during the season. So far only Hexis, which will be McLaren's lone representative in the GT1 World Championship, has publicly confirmed its program for the season.
"I'm really looking forward to the forthcoming season with McLaren GT and the opportunity to race the MP4-12C GT3," said Sims, 22. "I am delighted McLaren continues to support young drivers in their careers and I'm proud to join the likes of Rob and Alvaro [Parente] on the driver program for 2012."
Unlike Sims, Bell has a wealth of experience in GTs to fall back on, having won a pair of Le Mans Series GT2 titles with the JMW squad and finished second in the GTE-Pro class of last year's championship. The 32-year-old Brit has raced the McLaren before, having competed at the Spa 24 Hours last year in a factory-run car.
"I'm very excited to be joining McLaren GT and the opportunity to drive the new 12C GT3 in its first full season of racing," he said. "When I was invited to drive the car last year at Spa, I welcomed the chance to sample this new British racer. As I anticipated from a company that is synonymous with cutting-edge technology and a dedication to success, the car lived up to its expectations.
"It delivered the speed and showed the performance potential necessary to win in the highly competitive environment of sports car racing. I'm looking forward to contributing to further development of the car with a customer team when we take to the track at the start of this season."
Alvaro Parente, who completed most of the testing of the car and raced it last year, has extended his deal with McLaren while Oliver Turvey is expected to do the same in the near future.