Sarah Fisher Hartman Racing's Josef Newgarden is to gain a new team mate next month, with the team collaborating with RW Motorsports to expand to a two-car line-up for the GoPro Indy Grand Prix of Sonoma on August 25.

The team's second car will be in the hands of American Le Mans Series (ALMS) LMP1 championship points leader Lucas Luhr who will be making his d?but in the open wheel series.

"I am very excited about driving for RW/SFHR in Sonoma," said Luhr on Friday. "I have wanted to drive an IndyCar for quite some time and when this opportunity came up I was very happy to say yes straight away.

"I know I have a lot to learn in a very short time," Luhr added. "It's not going to be easy, but it's a great challenge. I know Sonoma having raced there in the past and I am looking forward to working with everyone at RW/SFHR and preparing for the race."

Team co-owner Sarah Fisher said that having Luhr on board was a positive step all round for the team and for regular driver Josef Newgarden.

"One of the big keys to success of this program will be the opportunity we will be able to provide Lucas for two days of testing," said Fisher. "It will be a great opportunity overall to give Josef the chance to work with a teammate."

"As we continue to raise the bar at SFHR, we are always looking for the next level to stay ahead of the curve," added team principal Wink Hartman. "Adding Lucas to the Sonoma event for us is not only exciting, knowing his championship abilities, but will give us a sounding board towards two-car efforts in the future.

"We know that's where we would like to be as a team, and this is one step towards our exploration of that ability," he added.

To ensure that Luhr gets seat time in an open wheel car before his IZOD IndyCar Series d?but, Luhr and SFHR will participate in a manufacturer test in Sonoma on August 13.

Luhr drives an HPD ARX-03a P1 prototype in ALMS for Muscle Milk Pickett Racing, making him familiar with Honda-powered cars, while RW Motorsports is a championship-winning USAC Silver Crown, Sprint, and Midget Series racing team.

"Bringing RW Motorsports to the top level of open wheel racing has long been a dream of mine, and through our partnership with SFHR, it has always been the intention to see that idea come to fruition," said Steve Weirich, owner of RW Motorsports

"Lucas has great strengths as well and I am looking forward to bringing a driver of his caliber to the IZOD IndyCar Series," added Weirich. "Sonoma is a great venue for us as well as IndyCar and we know the synergy of this entry will produce a great result."