Juan Pablo Montoya and Dane Cameron will share one of Team Penske's Acura ARX-05's in next year's IMSA SportsCar Championship.
Montoya quit racing in IndyCar full-time at the end of 2016 but stayed with Team Penske to compete in one-off events, such as the Indianapolis 500, this season.
Former Pro Mazda champion Cameron won the 2014 GT Daytona class of IMSA's premier championship before joining Action Express Racing and clinching last year's title with Eric Curran.
"Having Juan and Dane join our program brings together two drivers who have extensive sportscar racing experience in the prototype class and have already won at the top levels of the sport," said team owner Roger Penske.
The official unveiling of Acura's ARX-05 DPi racecar will take place on Friday as part of Monterey Car Week in California.
The full team will make its competition debut with the new Acura prototype sportscars at the 2018 season-opening Rolex 24 at Daytona in January.
Montoya, who has just completed the third of four tests for IndyCar as it signs off the new 2018 aerokit, will also be testing the new ARX-05 in preparation for next season.
"I have really enjoyed working with Roger and Team Penske over the last four years," said Montoya.
"When Roger asked if I'd like to be part of starting this new sportscar operation with Acura, it was an easy decision. I've always loved racing sportscars.
"It's definitely a challenge and it's going to be a lot of fun to develop a new car with Acura.
"I'm excited to start the testing of the ARX-05 next week. Team Penske started its winning tradition in sportscars and it's going to be cool to be a part of a new chapter with the team."
Cameron added: "Getting a chance to race for Team Penske is like a dream come true for a driver.
"To see all of the effort and resources that Acura Motorsports is putting into this new program to develop and win with the ARX-05, it's really impressive.
"It's going to be an awesome experience to add my name to the list of drivers who have driven for Team Penske. I'm looking forward to a busy off season and coming out of the gates strong at Daytona."