Ingram will enter the GT4 class in the MKH Aston Martin Vantage alongside Ron Johnson as the team also lines up on the grid for the first time.
Although Ingram, who heads into the BTCC finale at Brands Hatch this weekend still with a chance of defending his crown, has not raced in British GT previously, it would not be his maiden sportscar outing, after he raced alongside Johnson in a GTC-spec Ferrari 458 in GT Cup two years ago.
“Ron and I have done bits and pieces together for quite a few years, he's just a good mate,” Ingram told Autosport.
“I've raced with him in the [Citroen] C1s, we raced with FF Corse together at Snetterton in a Ferrari, and with Speedworks in the Supra. He's a nice guy to be around. He phoned, as he does, and said, 'Shall we go and do this?' and I said, 'Why not?'
“The first time I drive it will be in the test, probably on the Thursday, so I won't get a huge amount of time in it.”
Opting against setting a specific target for the outing, Ingram added: "We're not doing anything serious, this is just to have a play more than anything else.
“We're under no illusions that we're going to win, and I'm not interested in ruining anyone's day just to prove anything. Hopefully, we can just stay out of trouble and have some fun.
"They'll put a good car under us, and Ron and I can have an enjoyable weekend. It's awkward though - I'm officially listed as a gold but I'm not really gold in sportscars. We got a bit screwed there!"
This classification means that the pairing will be forced to either run with additional ballast in the Aston Martin or serve a ‘compensation time’ penalty during their mandatory pitstop.
Johnson is making his first championship appearance in a decade after last competing in the Donington finale in 2014.
“I’ve been looking at British GT for a while and would love to do a full season again,” he said.
“Donington feels like the perfect opportunity to see how I stack up against GT4’s usual suspects. And there’s no one else I’d rather share the car with than Tom.
"We’ve known each other for about a decade, done plenty of racing together, and I’m one of his BTCC sponsors. Believe it or not, he was also part of my Speedworks pit crew when I finished in the top 10 at the 2018 Aston Martin Le Mans Festival!”
