A few months since their TT podium, passenger Walmsley and driver Founds secured their best result to win the Southern 100 Isle of Man sidecar title.
Racing on the Colas Billown circuit, the pair beat world champions Tim Reeves and John Holden to become the first Lincolnshire winner of a Southern 100 title since Guy Martin.
The meeting attracts top solo riders and sidecar crews, but Pete and Jevan took control from first practice session on a damp Monday evening.
They posted the fastest time, heading main British Championship rivals Lee Crawford and Scot Hardy, with Reeves in third place.
Tuesday night’s practice session took place in dry track conditions and Reeves topped the leaderboard ahead of Pete and Jevan.
Race one was held on Thursday morning over a reduced distance after being red-flagged the previous night and proved an epic race.
Reeves took the flag followed by Alan Founds, Pete and Jev in third with just 1.2secs covering the top four.
The main S100 championship solo and sidecar races were run on Thursday afternoon, and Reeves false-started when jumping the lights.
Pete and Jevan left the line, fighting it out with brother Alan and Holden.
Going into Ballagegen Corner on lap two, Pete’s brother overshot, leaving Pete and Jevan to fight it out with the Sillicone crew of Holden and Manx passenger Lee Caine.
Holden’s outfit used its extra power down the straights, but Jevan and Pete countered with moves on the twists and turns of the bumpy Billown circuit.
Holden led across the line starting the final lap, but Pete pulled into his slipstream and stuck to the task, passing on the far side of the circuit.
As they rounded Castletown corner with just the run to the line, Holden’s machine was closing, with the advantage of its straight line speed.
But Jevan and Pete took the flag to complete a fantastic result to boost their hopes of one day winning the TT.
The races will be broadcast on ITV4 tonight and Friday at 8pm.
The riders wish to thank their sponsors Louth RandY Motors, and Parkinsons Fish Shop.
They are next in action in the British Championships over the weekend of August 3 and 4 at Anglesey.