Colburn will join younger brother Ben, Aaron Thompson and Finlay Robinson in the family’s Westbourne Motorsport line-up.
In the most recent rounds at Donington Park, Ben achieved his first top-three race result in the championship while Thompson was also able to battle for a podium position.
James now hopes his experience can to add support to their campaign at Croft. His outing there will be sponsored by Westbourne Motoring Assistance and Vantage Motor Group.
Notably, he will compete in the blue car that Ben drove last season; Ben is already in James's Terraclean/Gardx/Vantage machine from 2018!
The 26-year-old from Worthing, now joint Westbourne Team Principal with father Richard, commented: “I’ve always loved competing in the Clio Cup and Croft is one of my favourite circuits so it’s too good an opportunity to pass up.
“I’ll admit I also want to contest the one-off Clio Cup international race at the French Formula 1 Grand Prix the weekend after so this makes me eligible for a place on the grid there but that’s why Croft is important – it’s a chance to blow away the cobwebs, although there’s a chance I might do a few more rounds later in the year.
“Also, while I’m not contesting the full Clio Cup season, I’ll still be going to Croft aiming for some podium results and hope either through tactics on the track or feedback off it I can help our full-time drivers to move closer to a race winning situation.”
Croft’s two races will be rounds five and six of 2019’s 18-round Clio Cup season. Currently leading the standings are MRM team-mates Jack Young and Brett Lidsey.
Third is Max Coates – one of three drivers who will be competing in front of their home crowd at Croft. The others are his Team HARD team-mate Ethan Hammerton and Westbourne’s Finlay Robinson.