The long-time enduro specialist will team up with second-year driver Smith to complete a BJR's line-up that also includes Dale Wood, Dean Fiore and Chris Pither.
The deal marks a return to the Bathurst 1000 for Walsh, who sat out last year's race as he was preparing for a Certified Public Accountants exam.
He made four enduro appearances for BJR between 2016 and 2019, although missed the 2017 Bathurst 1000 as he recovered from a high-speed sportscar crash at Phillip Island the week before the race.
“I’m looking forward to being back on the grid this year at the Mountain and returning to BJR and joining Jack and the SCT crew,” Walsh said.
“I’ve known Jack for a while now, we met through super 2 when he started with BJR and we raced together in 2019 and since then we’ve been good mates on and off track.
“The Bathurst 1000 is one of those races where you never know what’s going to happen and anyone on that grid can cross the finish line first, so you just buckle in and see where you come out at the other end. Fingers crossed we have a good campaign and conquer the Mountain with a good position at the end of it.”