Foster thoroughly impressed with his defensive driving in the second contest after leader-on-the-road Zane Maloney was penalised for a false start.
As a result, Foster was battling for the lead and fended off Josh Skelton for the majority of the race until the final lap when he was unfortunate to lose out at the Club chicane.
That second race proved to be the highlight for the Cornish racer, who advanced to sixth in the Drivers’ Championship by virtue of a strong points haul.
Title contender Bart Horsten endured a difficult double-header of races on Saturday, but bounced back in Sunday’s encounter to progress to fourth at the chequered flag.
The Australian narrowly missed out on yet another podium by only a quarter of a second, and now holds a strong fifth position in the championship standings.
Alex Connor also had plenty of positives to take from the Hampshire circuit, with the 15-year-old continuing to impress and consolidating his second position in the Rookie Cup standings courtesy of a double points finish.
The F4 British Championship heads next to Knockhill, Fife, on the weekend of 14-15 September.
Arden British F4 Team Manager Gary Ward:
“All the drivers have improved from last time at this high-speed circuit in terms of driveability.
“Alex has gone extremely well, Tommy had a great race two and Bart bounced back to make some good progress in the last one.
“We will be back fighting for podiums at Knockhill in a few weeks time.”
Alex Connor (#27):
“It was a really good weekend – better than last time we were here. I think I made some good improvements just terms of pace and race craft as well.
“So far the championship has gone quite well, it’s my first season in British F4 so I’m just slowly making improvements and just kind of chipping away at it.
“To hold on to second in the Rookie Cup is great as well.”
Bart Horsten (#50):
“The last race was probably one of my best, I just misread the situation at the end because I didn’t know it was the last lap and could probably have got the podium off Louis [Foster] but he drove really well.
“A tough weekend – I put in a lot of work for this one, and the team put in a lot of work leading up to it – to find the pace in the car.
“We were a bit behind here last time, especially in myself, my pace in the car wasn’t quite right around this track. So at least we made progress there.
“It’s disappointing but I tried my heart out this weekend. You have weekends like this, and although I haven’t had the best run recently, I think I’m learning a lot as a racing driver and that’s what this series is about.”
Tommy Foster (#53):
“I’m really happy with the result from race two, obviously disappointed not to get the win but over the whole weekend we had a decent haul of points.
“It wasn’t the most points I’ve ever scored, but it wasn’t the least, and we’ve moved up a place in the championship.
“I’m feeling comfortable with the car now, we’ve got huge pace. We just need it all to fall into place, which it should do going forward.”