A set of four programmes, telling the story of Mobil 1 and its importance to teams across the classes at the Le Mans 24 hours.               Jim Roller talks to Pascal Vasselon:   John Hindhaugh speaks with Porsche’s Andreas Seidl:   Shea Adam meets Corvette’s Doug Fehan:   John Hindhaugh catches up with Mobil 1’s Bruce Crawley: