E.J. Viso and Sebastian Saavedra (photo), who competed in the 2013 IndyCar Series season, were late additions to the Starworks Motorsports (Prototype class) team for the Rolex 24 at Daytona.
It gives the race 32 drivers who have started at least one Indy car event.
Saavedra, 23, of Colombia, who had a best finish of eighth for Dragon Racing last season, said he's hopeful of announcing plans soon for the 2014 IndyCar Series season.
"Anything that has wheels, I'm ready to do it," said Saavedra, who is making his debut in the race. "This was a late-minute situation, but it's an opportunity that I was going to let go by. My goal is IndyCar and we're working to make that happen."