Alexander Wurz's lap of Spa-Francorchamps.

McLaren-Mercedes test driver Alexander Wurz describes a lap of Spa-Francorchamps - site of this weekend's Belgium Grand Prix:

''Crossing the start-finish line on the short pit straight at Spa-Francorchamps, you build up to a top speed of 180mph/280kph in fifth gear before braking hard for La Source hairpin. The tight righthander is the slowest point on the track and is taken in first gear at 35mph/56kph.''

McLaren-Mercedes test driver Alexander Wurz describes a lap of Spa-Francorchamps - site of this weekend's Belgium Grand Prix:

''Crossing the start-finish line on the short pit straight at Spa-Francorchamps, you build up to a top speed of 180mph/280kph in fifth gear before braking hard for La Source hairpin. The tight righthander is the slowest point on the track and is taken in first gear at 35mph/56kph.''

''Exiting the hairpin you accelerate downhill, reaching 185mph/296kph on seventh gear on the approach to Eau Rouge. Perhaps the most challenging corner on the calendar, Eau Rouge is taken flat out in qualifying as you climb steeply left then right at speeds up to 180mph/290kph in seventh gear, pulling 4G, the highest on the track. It is important to maintain your speed through Eau Rouge as it leads onto the Kemmel straight reaching 205mph/328kph as you power up through the gears on the approach to the right-hander of Les Combes, which offers one of the best overtaking opportunities at Spa.''

''It is immediately followed by the Malmedy chicane, your speed drops to 105mph/168kph in third gear through the left-right flick. A quick burst of acceleration along a short straight sees you reach 169mph/272kph in fourth gear before braking for the long right-hander of Rivage. Taken at 69mph/112kph in second gear, the track drops as you negotiate Rivage, which is off-camber and can cause problems with understeer.''

''Shortly after the exit of Rivage, the track takes you left at a speed of 103mph/160kph in third gear before accelerating along the short straight that takes you to Pouhon, reaching 185mph/296kph in sixth gear. Entering the fast double left-hander at 133mph/215kph in fourth gear, your speed increases to 170mph/272kph in fourth gear through the corner. Hard on the throttle you reach 190mph/305kph in seventh gear before braking hard for the right-left chicane of Fanges. The first section is taken at 85mph/136kph in third gear, and the left flick at 105mph/169kph still in third.''

''Another short burst on the throttle sees you reach 155mph/248kph in fourth gear on the approach to the double right-hander at Stavelot. You enter the bumpy downhill corner in third gear at 95mph/152kph before accelerating to 150mph/240kph in fourth gear as you exit. Powering up through the gears as you head back towards the pits negotiating the long, fast sweeping left-hander of Blanchimont, which is taken flat out in seventh gear, reaching 200mph/320kph. You then brake hard for the sharp left-right-left Bus Stop chicane, which is negotiated at 55mph/88kph in second gear, using the kerbs to get the best line through the chicane, you then accelerate back down the pit straight and off for another lap...''

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