The unique and spectacular challenge of Knockhill (Fife) is the next destination for the Porsche Carrera Cup GB for rounds 13 and 14 over the weekend of 15/16 August.With an excellent 20-car field, including five Scottish or Scotland-based drivers, there is sure to be some great racing as the three title races start to build towards a climax. Proudly flying the Saltire are Glynn Geddie from Aberdeen, Derek Pierce from West Kilbride and George Brewster from Edinburgh as well as Aberdeen-based Tommy Dreelan and Bob Lyons. While the home fans have plenty of interest in the pair of races, there is a fierce battle going on at the head of the points' table as four drivers fight over the 2009 title. After a superb weekend at Snetterton, Tim Harvey (Red Line Racing) has gone back to the head of the standings but has just five points in hand over Tim Bridgman (Team Parker Racing), while James Sutton (Red Line Racing) and Michael Caine (Motorbase Performance) are also strong contenders.Knockhill is notorious for shaking up the title race, with a challenging track and sometimes-unpredictable weather. Bridgman took a win and a second at Knockhill last year and will be determined to turn the tables on Harvey after the former BTCC champion dominated the Snetterton weekend.Sutton and Caine, meanwhile, will be looking for Harvey and Caine to hit problems in order to give them a chance of closing the points' gap as the championship heads into the final eight races of the season. Add in Charles Bateman (Team Parker Racing) and Carrera Cup Scholarship winners Tom Bradshaw (Team Parker Racing) and Lewis Hopkins (Red Line Racing) and it is a very strong line-up for the pro category.Geddie (Team Parker Racing) is the man of the moment after a superb double pro-am1 victory at Snetterton and he will go to Knockhill bubbling with confidence. Glynn only turned 19 in June, and so he is one of the new young stars of the Carrera Cup. That double win at Snetterton took him closer to pro-am1 pacesetter Robert Lawson (JHR), and the points' gap is down to 18, although Tony Gilham (Red Line Racing), Ollie Jackson (Motorbase Performance) and Pierce (JHR) are firmly in the battle as well.Dreelan is another pro-am1 contender, while Lyons and Brewster both race in pro-am2, which is for cars from before 2008. All three of them race for the Montrose-based Celtic Speed team, which is managed by Alan Keith, a well-known racer at Knockhill in his own right. Lyons is chasing the pro-am2 title and still has ground to make up on Robin Clark (Parr Motorsport), but Lyons has the pace to win this weekend on a track he knows well. Meanwhile, Brewster made an impressive Carrera Cup debut at Croft in June when he took a pro-am2 double. However, the absolute pro-am2 pacesetters could be Paul Hogarth (IN2Racing) and Glenn McMenamin (Parr Motorsport), who shared the wins at Snetterton after some fabulous battling.All of them know that Knockhill is often a turning point in the season-long contest. The challenging track and changeable weather can dramatically alter the positions and with only six races left after the weekend in Scotland, there is much at stake.