Calum Lockie and Peter Sowerby claimed a resounding victory in the biggest race of the weekend during the magnificent Silverstone Classic (26/27 July) when they won the David Leslie Memorial race in Sowerby's Group C Nissan RC90K.The 90-minute two-driver race brought the curtain down on the biggest historic racing festival that Britain has ever hosted and capped a tremendous weekend for the whole team. "It was very poignant that it was for the David Leslie Trophy," said Calum of his fellow Scot. "We knew David very well and we had been team mates."For Sowerby, it was a stunning weekend as he bagged two victories in the FIA Historic Formula One Championship in his Williams FW08 and also finished fourth in the Group C sprint race on Saturday afternoon.But it was Sunday's 90-minute Group C race that was the big event and the team's weekend started with a misfire during testing on Thursday. In qualifying on Friday, Calum did the new tyre run and had to cope with a lot of slower traffic with more than 30 cars on the track. "I had to be very careful with the slower cars," said Calum. "We were getting nearly 190mph into Stowe and 180mph before Copse. Bridge was flat in fourth gear!"Calum finally got a reasonably clear lap and, despite the on-going misfire, set a time good enough for fourth on the grid. After qualifying, the team continued working hard to resolve the misfire and had the car running cleanly in time for Saturday's 30-minute sprint race. Despite a problem with oversteer, Peter brought the car home in an excellent fourth place.As the curtain closer for Sunday's racing, the Group C race started at the hottest part of the afternoon. Peter did the opening half of the race, making a steady start while the front tyres came up to temperature and then upping his pace to bring the car into the pit stop in second place. "Peter drove a fantastic stint and I went out still in second place," said Calum.With the car feeling quite different now that the misfire and oversteer problems had been improved since qualifying, Calum took a couple of laps to settle back in to the car, but was soon pushing hard in pursuit of the leading Jaguar of Chris Buncombe. Then, he came up behind the Spice of Martin Stretton, which was dropping a lot of oil. "He covered my screen in oil and I really couldn't see very much," said Calum as everyone started to struggle badly on the incredibly slippery track. "With 800bhp on an oily track, the conditions were very difficult and I had three or four big moments," said Calum.Knowing that they were holding a secure second place, Calum eased his pace back considerably, but soon found that everyone else had done the same. "Eventually the oil started to clear and I started to pick up the pace, and I was closing on the leading Jaguar but he was 25s ahead and there weren't enough laps left. Then I saw this Jaguar parked at Chapel and soon got P1 on the pit board. We'd lapped the entire field by the finish."In what was thought to be the first ever Group C win for Nissan, Calum and Peter had won the David Leslie Memorial Trophy and David's widow Jane was there to present the awards on the podium. "There are some definite highlights in my racing career and this was a very, very special win."Along with the trophy, Jane Leslie presented them with a Saltire flag of Scotland, which had previously been used as a curtain in the loo at the Leslie family home. "I loved that," said Calum. "It was a brilliant weekend with a great atmosphere, so a really big thanks are due to Motion Works and the HSCC for all their work," said Calum. "I'm indebted to Peter for sharing this amazing car with me and to the whole team at CGA Engineering for working so hard. I'm also grateful to Dunlop for great tyres and my other supporters, Brian James Trailers, Grand Prix Racewear and Porsche Centre Silverstone."The final weekend of the Group C season will be at Donington Park on 4/5 October.