Races five, six and seven in the Michelin Porsche Open Series will take competitors to Spa-Francorchamps over the weekend of 4/5 June for a challenging triple header at what many drivers consider to be the finest track in the world.The Porsche Club GB has arranged no less than three races at the stunning Belgian track, with the third race running over 50 minutes and offering the chance for two drivers to share cars in the Open.Three cars stand out at the head of the field and it is the 935 of Richard Chamberlain that should set the pace. Although the car suffered some cosmetic damage at Oulton Park recently, Chamberlain and the Chimp Tune team will have the fire-breathing monster back in full fettle in time for the trip across the channel.Set to line up against Chamberlain is Peter Cook in his 911GT2. They clashed and both retired on the opening lap at Oulton Park, so battle should be rejoined in Belgium. Cook has already raced at Spa this season in the 996 he is using in the Belcar Championship, so he will be quickly up to speed when qualifying starts.When Cook and Chamberlain clashed at Oulton, Rupert Lewin (996 GT2-R) swept to a commanding victory and will be eager to unleash his superb racer on the straights and fast corners at Spa. Meanwhile, Paul Howells (911GT2) finished second to Lewin in Cheshire and now makes the trip to Spa.Paul Hogan was a double winner at Snetterton in his 996 Turbo and faces a class two challenge from racing newcomers Mark Stephenson and Mark Albutt in a brace of 911GT3 Cup cars. However, the seasonal debut of Craig Rapp in his 911GT3 Cup will surely turn the class two form on its head. GT racer Aaron Scott is scheduled to share with Hogan in the two-driver race.John Allen (993 Super Cup) heads the class three field, which features the return of the similar car of Steve and Mike Burtt following a major engine drama at Snetterton at the start of the season.