The fastest circuit on the calendar is the setting for rounds three and four of the 2005 Carrera Cup GB as the championship heads south to Thruxton in Hampshire over the weekend of 30 April/1 May.Heading the field to Thruxton, where average lap speeds in the Porsche 911 GT3 Cup cars top 110mph, is Richard Westbrook (Red Line Racing). Having won both of the opening races against a fierce challenge from his arch-rival Tim Harvey (Team RPM), Westbrook has seized the early points' lead in the title race. With a road-going Porsche 911 Carrera up for grabs at the end of the season, there is a lot to play for!However, Westbrook missed the all-important pre-race test session at Thruxton a month ago as he was away racing in the Porsche Supercup in Bahrain. That means Richard will head into qualifying on Saturday afternoon with a lot of work to do in just 20 minutes. He will also race at Thruxton in between races in the Supercup. The weekend before he will be racing at Imola (Italy) in the F1 support race and the weekend after Thruxton he will be racing at Barcelona (Spain).Harvey finished both races at Donington right on Westbrook's tail and, had the second race been a couple of laps longer, the result could have changed as Harvey's car got stronger and stronger over the race distance. Thruxton is a challenging track - for driver, car and tyres - and Harvey will be very determined to claim his first win of the season. Westbrook and Harvey shared the wins at Thruxton in 2004.Fastest in the Thruxton test at the beginning of April was Jason Templeman (Team Parker Racing) when he set the fastest ever Carrera Cup lap of the circuit. Jason didn’t have a great weekend at Donington and a couple of fourth places is less than should be expected from the SAS International-backed racer. He will be expecting more from the Thruxton races. Alongside Templeman in the SAS-backed team is Damien Faulkner and he was very close to Templeman's pace in testing, so the pair of blue and white cars should be right with Westbrook and Harvey in Hampshire.Leading the chase of the 'big four' at Donington was Nigel Rice (Red Line Racing) and he showed the speed needed to get in amongst the leading quintet. Rice was a podium finisher at Thruxton in 2004 and could do the same again this year. Meanwhile, his Red Line Racing team mate Jason Young had a great weekend at Donington and earned the 'driver of the day' award for his pace.Completing the Red Line Racing squad is Stephen Shanly, a former race winner at Thruxton in National Supersports. He had a torrid time at Donington when an accident in testing masked his true speed and he is aiming to put that straight at Thruxton.Another promising championship newcomer is Emmanuel Crouvisier (Team RPM), who is gaining speed with every outing in the Porsche, while Steve Clark (Team RPM) is also building his pace and experience. Both of them will be racing at Thruxton for the first time, so solid points scores will be their main aim. Joining Crouvisier and Clark with limited Thruxton experience will be the Trackspeed pairing of David Ashburn and Rory Fordyce.Finally, The Porsche Cars VIP entry with Team Autosport will be driven by Southampton ace Jon Barnes. The former Caterham champion has been given a fabulous chance to show his potential at Thruxton and plans to make the very most of the opportunity