Weather became a serious factor in the fourth hour at Silverstone a rain shower prompting a wave of cars electing to pit for wet tyres, only for many to return for slick tyres when they realised the rain wasn't heavy enough to make the treaded tyres worthwhile.
The main casualty of the hour came in the lowest class – class 4. Having led the class through both the practice and qualifying sessions and only just trailed at the end of the previous the hour the BPM Racing Limited SEAT found itself the victim of punt at Maggotts that broke the front suspension, starting a steady plummet down the order as the car remained in the pits at the end of the hour having dropped to 50th overall, all but losing the chance of taking class honours.
There were also high profile problems among the GT4 cars. The Intersport BMW continued to lead, now a commendably high sixth overall. The Neil Garner no.42 Porsche had maintained second place with the AMR Jota Sport car in third.
However, both the RJN Nissan and Team Lotus entries had struck trouble. The Evora faced with a three to four hour fix of the gearbox and the Nissan squad struggled with a recurring problem. “It’s a fuel pressure issue, the same problem we’ve had all year,” said driver Lucas Ordonez. “Only, this time, it's the pump that has failed. The guys have just replaced it and we should be out soon, but we’re already down to 34th and we could be here another 15 minutes”
Up front the Aquila remained ahead, Phil Bennett one of the main exponents of slick tyres when other were on wets, as well as Andy Neate, who was over ten seconds faster than the no.8 Ferrari in his chase down for third place at the time.
The seemingly unstoppable Jet Alliance Porsche remained in the lead among the Class 2 cars, the Marcos challenge against them halved the Chesterton example in the garage after “two big bangs” from the rear of the car.
The Team LNT Ginetta was leading the Production Class, ahead of the Chimp Tune Lotus – the car that came to a firey halt in night qualifying repaired overnight.
Class Standings After Four Hours
1 – No.3 Wessex Vehicle – Aquila CR1
2 – No.8 MJC Limited – Ferrari 430 GTC
3 – No.1 Topcat Racing – Mosler MT900
1 – No.22 Jet Alliance – Porsche 997
2 – No.21 Topcat Racing – Marcos Mantis GT3
3 – No.19 Chesterton Commerical Holdings – Marcos Mantis GT3
1 – No.39 Intersport – BMW M3 E46
2 – No.42 Neil Garner Motorsport – Porsche 996 GT3 Cup
3 – No.38 AMR Jota Sport – Aston Martin N24 GT4
1 – No.83 Team LNT – Ginetta G40
2 – No.82 Chimp Tune Racing – Lotus Elise GT4
3 – No.91 Mardi Gras Racing – Honda Integra