The #2 Audi Sport quattro S1 competed in Group B class of the 1986 World Rally Championship season. It is part of the 1986 E2 revision which significantly upgraded the original Audi Sport quattro in order to match it to increasingly more powerful competition in Group B and make it viable in the Pikes Peak Hill Cimb racing series.
This was the car that put Audi rallying on the map. Introduced in late 1985 as a Group B entrant, the quattro S1 began a string of incredible performance that helped define the near mythical status that Group B regulations still enjoys among rally enthusiasts. The quattro S1 was one of the most powerful Group B cars ever made, with its turbocharged engines producing power north of 460 horsepower. Little wonder that, in addition its rally popularity, the quattro S1 also held multiple world records on the Pikes Peak International Hill Climb during the late 80s, and is still widely regarded to this day as one of the most incredible race cars Audi has ever built.
The body of the Sport quattro S1 was heavily modified with extended fenders and large spoilers at both front and rear to produce a much higher amount of downforce than the original Sport quattro. Its chassis received a shorter wheelbase along with a kevlar body shell, improving turn-in steering and reducing weight to 2403 lb (1090 kg). The predecessor's front-biased weight distribution was tacked on by relocating the radiator to the rear, resulting in only 52% of weight up front.
The Sport quattro S1 reuses the turbocharged 2.1 litre engine from its predecessor but with power increased to 469 hp (476 PS; 350 kW) and 354 ft·lb (480 Nm) of torque. Its high specifications allow it to go 0 to 60 mph in only 3.1 seconds and 7.2 seconds from 0 to 100 mph and puts it among the fastest rally cars in the Forza series.