The Heritage Grand Touring Car Challenge is a sell out for 2007 and such has been the demand for entries that the series organisers have had to turn prospective competitors away, even though the opening race is still more than two months away.With 50 cars registered for the season and grid capacity ranging from 36 to 44 cars for the seven-round season, the organisers are currently unable to accept any more registrations. However, a waiting list has been created for hopeful racers should any gaps appear during the season. "We have been overwhelmed with applications to join our series and are now in the lucky position of being over-subscribed," said series founder and director Roger Bennington of Heritage Racing Support. "We apologise to those who were unlucky not to be able to secure a place this year. It is therefore not surprising to find that we have already had applications to register for 2008!"Interest in the series for saloon and GT cars of the 1960s and 1970s has boomed in recent times, boosted by a 2007 programme that includes races at the A1 GP and WTCC events at Brands Hatch as well as high-profile meetings at Snetterton, Silverstone, Donington Park and Spa."We are very pleased to have been able to offer such a fantastic calendar and very much appreciate MSV's efforts and support in putting this together," said Bennington. "We now have to ensure that we put on a fantastic day's racing for the spectators."With entrants needing to commit to races well in advance, just about all of the seven events now have capacity entries. "Whilst there are a lot of interesting cars out there that we would like to bring in, we want to give priority to those who have supported the series in previous years," said Bennington. "We look forward to welcoming them back, as well as our new competitors at Donington Park in April."