Wilson confirmed at Andretti for 2018 Indy 500

Stefan Wilson, who gave up his 2017 Indy 500 seat to Fernando Alonso, will return for the 2018 500 in the No. 25 Andretti Autosport Driven2SaveLives Honda.

"Really excited to get back to Indy," Wilson told RACER at Sonoma. "We've been working really hard on that ever since May this year...I feel really determined to get back there and put on a bigger performance."

• The key to Alonso's deal? Stefan Wilson

Wilson, who hopes to parlay this into additional races in 2018, has spent months trying to build relationships with sponsors, calling it "a roller-coaster ride."

"I'm very excited to be officially joining the Andretti Autosport team for the 102nd Indy 500," he said. "It has been a roller-coaster ride to get here, but when looking back, I'm really pleased and feel very fortunate to be in the spot I'm in now. I've just kept thinking about the future, knowing that I'd be joining one of the most successful teams in Indy."

"We're really happy to welcome Stefan back to Andretti Autosport and proud to see him running the No. 25," added Michael Andretti. "While not on track, Stefan was a big part of our Indy 500 effort in 2017, and we're looking forward to getting him back behind the wheel at the Indianapolis Motor Speedway."

The 500 will mark Wilson's third in the Verizon IndyCar Series, two of them coming at the speedway.

Wilson will partner with Indiana Donor Network to advance their Driven2SaveLives campaign helping to promote awareness of the importance of organ, tissue and eye donation and transplantation.

"Ultimately, we are working to register more donors," Wilson said. "Organ donation and transplantation is a cause I'm connected to through the loss of Justin, who saved five lives. We'll be working with Driven2SaveLives to provide hope to patients on the national wait list, and honor donor heroes."

As part of Wilson's decision to step aside for Alonso, IMS has partnered with the IDN on a year-long campaign to raise awareness for organ donation. IDN and its Driven2SaveLives campaign was first introduced to IMS in 2016 as Wilson's primary sponsor for the 500 entry, which came after the organization learned of the multiple organ donations made by his late brother Justin Wilson, who died following a crash at the Pocono IndyCar event in 2015.

"Stefan is uniting race fans and elevating the conversation around donation and transplantation, and with his help, we hope to get more people across the country to register their decision to donate," said Kellie Hanner, president and chief executive officer at Indiana Donor Network. "We are grateful for his efforts."

This isn't the first time Wilson has raced for Andretti. Fourteen of his 32 Indy Lights starts came with Andretti Autosport and included two wins and five podiums in 2011.

"Andretti Autosport and I won a few [Indy Lights] races together but came up short in the 2011 championship hunt," he said. "Since then, my career has been a bit of a rocky road. It's taken a tremendous amount of determination, and that determination only grew stronger when we lost Justin. In a way, I feel like I'm racing for him as much as I am for myself. I do want to succeed in my own career and prove that I belong, but also, I want to do something he never got the chance to, I want to win the Indy 500. That's part of what drives me.

"I really want to thank Mark Miles, Doug Boles, Michael Andretti and the rest of the Andretti Autosport organization. A lot of the agreements were initially done in good faith, and I'm very thankful for all the effort that has brought us here."

Marshall Pruett contributed to this report.