The long awaited return of live FIA World Endurance Championship coverage heads our sportscar line-up this weekend as LMP1 heavyweights Audi, Toyota and returnees Porsche square up for the 6 Hours of Silverstone, the first bout of an eight-race encounter. Audi are chasing a third successive British triumph with title-holders Tom Kristensen and Loic Duval aiming to repeat their 2013 Tourist Trophy victory alongside newcomer Lucas di Grassi. Meanwhile Porsche’s 919 Hybrid signals Stuttgart’s top-tier return, although Toyota will be eager to give the German duo a knockout blow with their TS040 Hybrid. The European Le Mans Series’ season opener consolidates the grand prix venue’s endurance racing roster as Signatech Alpine begin their LMP2 title defence with defending drivers’ champion Nelson Panciatici. British squad Jota Sport triumphed in last year’s rain-shortened race, while 16-year-old American Matt McMurry makes his debut with Peterborough-based Greaves Motorsport.Completing the Northamptonshire circuit’s action-packed weekend, the High Speed Television Channel has live FIA European Formula 3 Championship coverage of the season’s first three races. All eyes are on Mucke Motorsport’s Felix Rosenqvist as he tries to claim the championship after finishing third and second in the previous two years. However the Swede’s title hopes could be dashed by karting sensation Max Verstappen, son of former F1 driver Jos, who has made a storming start to his single-seater career in pre-season testing. Moving swiftly from Italy to Bulgaria, the FIM Motocross World Championship continues with delayed-as-live action from Sevlievo. Following his clean sweep at rounds one and two, MXGP world champion Tony Cairoli struggled last weekend as Gautier Paulin and Clement Desalle took victory in moto’s one and two respectively.Meanwhile in MX2, Jeffrey Herlings blew the cobwebs away on his return from injury with a win and second place, vaulting Holland’s title-holder to third overall and only 10 points behind series leader Arnaud Tonus. Finally, we have first-round highlights of the Lamborghini Super Trofeo from Monza as former champion Cedric Leimer and Andrea Amici try to repeat their 2013 victories at the Italian Grand Prix venue in the Gallardo LP 570-4 Super Trofeo.Saturday 19 April10:10 LIVE FIA Formula 3 European Championship, Rd 1, Silverstone (Race 1)13:10 LIVE FIA Formula 3 European Championship, Rd 1, Silverstone (Race 2)14:10 LIVE European Le Mans Series, Rd 1, Silverstone20:00 Lamborghini Super Trofeo, Rd 1, Monza – Highlights 21:00 FIA Formula 3 European Championship, Rd 1, Silverstone – Replay (Race 1&2)Sunday 20 April09:05 LIVE FIA Formula 3 European Championship, Rd 1, Silverstone (Race 3)11:30 LIVE FIA World Endurance Championship, Rd 1, Silverstone18:30 FIM MX2 Motocross World Championship, Rd 5, Bulgaria – Delayed-as-Live19:30 FIM MXGP Motocross World Championship, Rd 5, Bulgaria – Delayed-as-Live22:35 FIA Formula 3 European Championship, Rd 1, Silverstone – HighlightsAll times are BST