The pairing is the first which the Yatala-based squad has confirmed for this year’s enduros, and comes after O’Keeffe tested with MSR at Queensland Raceway in recent weeks.
The Melbourne-based driver is currently competing in both Supercheap Auto TCR Australia and Porsche Carrera Cup Australia, scoring a win in the former and pole in the latter so far this year.
His start in this October’s Bathurst 1000, driving the #10 Bendix Camaro, will be his fifth in a row in the Great Race.
“I’ve always watched Dylan’s racing career closely and thought he has been a stellar co-driver over the years,” said team owner Matt Stone.
“We’re excited to now have him join the MSR team this year in Car #10 alongside Nick as we have a red hot crack at the enduros.”
Percat said, “We’ve locked in Dylan O’Keeffe as our co-driver for this season’s endurance campaign, which is really cool.
“He is the right height so that works for me, he’s doing plenty of racing with TCR and Cup cars as well and he’s a really good fit in the MSR team.
“Pumped to have him onboard the Car #10 crew; he’s always done a really solid job at Bathurst and Sandown so I’m looking forward to seeing how we go.”
O’Keeffe made a sudden Supercars Championship debut for Garry Rogers Motorsport when Richie Stanaway was benched for the Sunday of the Gold Coast 600.
His previous starts in the Bathurst 1000 have come with Kelly Racing, Tekno Autosports, and, for the last two years, PremiAir Racing.
“When the opportunity came to join the Matt Stone Racing squad for the enduros, I jumped at the chance – they’re definitely a team on the rise,” declared O’Keeffe.
“They’ve won races the last couple of seasons, and Nick’s been in great form this year.
“They’re a well-drilled team, very organised and methodical and it’s an enjoyable environment to be part of. It was my first time working with Nick, but we were already gelling really well during the test day.
“He’s obviously very experienced and has a great record at Bathurst – as well as his debut win in 2011, he’s finished on the podium a couple more times so I’m really looking forward to tapping into his knowledge base and learning as much as possible from him.”
MSR is yet to confirm Cameron Hill’s co-driver in Car #4 although Cameron Crick is expected to land the seat.
The Penrite Oil Sandown 500 takes place on September 13-15 and the Repco Bathurst 1000 on October 10-13.