Tom Onslow-Cole has made a surprise move to the AmD Milltek squad for this year's British Touring Car Championship.
Onslow-Cole, who won four times on his way to fourth in last year's championship, will race the team's Volkswagen Golf, which will be powered by a Lehmann-tuned NGTC engine.
"It's a tremendous signing for us," said AmD team principal Shaun Hollamby. "Tom is one of the top 10 touring car drivers in the world, in my opinion. He's won in every car he's driven in the BTCC and he can be the catalyst to really drive us up the grid.
"The car has always handled well, and the NGTC engine should give us a boost of around 60bhp on last year, so our aim is to become a consistent top-10 finisher. I'm sure Tom has the ability to help us to do that."
Onslow-Cole had been strongly linked to a drive with Motorbase Ford and also tested a SEAT for Special Tuning Racing at Silverstone earlier this month, but has instead joined AmD, which made its BTCC debut last year.
His deal means that Hollamby, who raced the Golf last year, will step back from driving duties to focus on his role as team principal.
"It was a tricky decision, but I'm not running this team as an ego trip for me," he added. "I can see that there's a huge advantage to me stepping back and a proven race-winner getting in the car.
"It's a risk for him, and a year ago, I'd never have dreamed he'd have even considered joining us. But we're a team that's getting more experienced by the day, and I think we can be a very good fit for each other."
Hollamby confirmed that the car will have a shakedown at Brands Hatch on Wednesday before having a full day of running at the official BTCC test at Silverstone the following day.