The biggest challenge in the history of the Porsche Carrera Cup GB awaits the drivers as the series heads to the Nurburgring Nordschleife for round nine of the championship during the Porsche Carrera World Cup (Saturday 25 June).This record-breaking race will present Carrera Cup GB racers with the chance to tackle the track that is widely-regarded as the finest and most daunting in the world, with 88 corners packed into 14 miles of twisting track in the Eifel Mountains in Germany. To race on the Nordschleife is the dream of many drivers and the Carrera Cup racers will tackle a six-lap, 85-mile race on Saturday in the build up to the annual Nurburgring 24-hour race.The Nordschleife is a track that rewards experience and from the Carrera Cup GB ranks it is Tim Harvey (Nationwide/Motorbase) who stands out as having the greatest knowledge of this remarkable race track. That level of prior track knowledge marks Harvey as a pre-race favourite, but over recent weeks the leading title contenders have all been gaining experience of the Nordschleife and a final round of familiaristion training is taking place this week.Heading to Germany with a handy points’ lead is James Sutton (SAS/Redline), who has a 20-point margin over team mate Michael Meadows. However, it is far too early for Sutton to be thinking about a second Carrera Cup title and his aim for the Nurburgring is another strong points’ finish. Meadows, meanwhile, is having his best season to date and knows that he cannot afford to let Sutton add to his lead as the series heads into a seven-week mid-season break.Two drivers from the Parker with Juta team are taking the fight to the SAS duo and both Stephen Jelley and Euan Hankey are determined to use the wild card of this race on the Nordschleife to peg back the points’ gap. The experience of the track acquired by Stuart Parker and his team over the last decade could prove crucial in Saturday’s race. Ben Hetherington (Oman Air/Redline) and Team Parker Racing’s Sam Tordoff and Richard Plant are new to the track as well, but are all capable of claiming a podium place.In Pro-Am1, Jonas Gelzinis (Juta Racing) is setting the pace and that is likely to continue in Germany, where he may well be right up among the pro drivers. Chasing Gelzinis are Ahmad Al Harthy (Oman Air/Redline) and Rory Butcher (Celtic Speed) and Butcher heads to Germany on the back of a stunning performance last time out in changing weather conditions at Oulton Park.With Pro-Am2 leader Andrew Shelley (Redline Racing) missing the race due to family commitments, it is George Brewster (Celtic Speed) and Keith Webster (Redline Racing) who are poised to take over the Pro-Am2 lead. Other Pro-Am2 podium contenders are Richard Denny (Parr Motorsport) and Tommy Dreelan (Celtic Speed).After qualifying at 15.25 on Friday, the Porsche Carrera World Cup will start at 11.20 on Saturday. Eurosport will carry a live TV broadcast of the race in a programme starting at 10.45 (local time).