Foster had finished second on the road but then inherited his first win after provisional winner Luke Browning was penalised post-race for a false start.
Subsequently, the Cornish racer’s successful defence from Josh Skelton in a photo finish paid even greater dividends, with the winning margin an unbelievable 0.099 seconds.
Championship challenger Bart Horsten endured a mixed weekend at the 2.99-mile Norfolk circuit, running in contention for a second win of the season in race two before unfortunate contact with Zane Maloney at Murrays dropped him to tenth in the final reckoning.
Horsten then bounced back in the final encounter as the Australian produced a defensive masterclass to fend off race-long pressure from Skelton, coming home second to reward the Banbury-based squad with further silverware.
Alex Connor continued his impressive run by securing a Rookie Cup win in race two when he progressed from ninth on the grid to finish fifth.
The net result of that saw him rise to second in the class standings, especially remarkable given the 15-year-old was forced to miss the season-opener due to his age.
The F4 British Championship resumes at Thruxton, Hampshire, over the weekend of 17th-18th August.
Arden British F4 Team Manager Gary Ward:
“I’m really pleased for everybody and all three drivers. As a team we’ve worked really hard to get them up there.
“Tommy has broken his duck, he’s got his win now which is great and I’m really pleased for him. Alex is really growing as well, some absolutely fantastic racing from him, proper driving!
“Bart Horsten has done a superb job this weekend, in race three he drove one of the cleanest defensive races I’ve ever seen. He didn’t put a wheel wrong.
“I think that’s going down as one of the best races out there in terms of clean racing, so I’m really pleased with the weekend. It was really exciting and great for all the team at Arden Motorsport.”
Alex Connor (#27):
“It’s been a really good weekend for me, some good points and especially for the Rookie Cup.
“I feel like I’ve improved a lot since Donington Park which was my first race weekend. I’ve gained a lot more confidence in the car; a lot more confidence when overtaking.
“I think I can push myself now for at least second in the Rookie Cup – that would be a good result.
“We’re performing very well as a team, we drivers are working well together as team-mates and hopefully it stays like that for the rest of the year.”
Bart Horsten (#50):
“I was a bit distraught that I didn’t do well in the two races earlier this weekend, but it’s been a really big turnaround.
“I would have loved a win but a second place is a step in the right direction. We knew the team had a good foundation, it was just sorting out little kinks.
“I think we’re getting better in terms of how we conduct ourselves and organisation, as well as communication which is a big thing as well.
“We should be a force to be reckoned for the rest of the year because I think we probably got the most points out of all the teams this weekend. It’s been really good.”
Tommy Foster (#53):
“Obviously we finished second on track so I was quite happy with that, and then I had no expectation for Luke [Browning] to get a penalty but he got a false start.
“It’s unfortunate for him but I’m not complaining! I feel like it’s been a long time coming, it’s just finally nice to have it accomplished. I’ve just got to go out there and get another win now!
“I’m really looking forward to Thruxton, I think now with everything going well we can get right up at the sharp end and challenge for the wins.”