The Focus RS Mk1 was produced from October 2, 2002, to November 11, 2003, and was Ford's return to the RS (Rallye Sport) badge after the demise of the tweaked Escorts, particularly the fabled Ford Escort RS Cosworth. Production was limited to 4501 units only. The car was largely built on its own assembly line in Ford's Saarlouis plant, with some additional specialist off-line assembly performed by the ACÜ group at Überhern. The RS was offered all over Europe, but 2147 were sold in the United Kingdom, by far its largest market.[49] The Mark 1 Focus RS was a limited production run available in 21 European countries. Using a turbocharged version of the 2.0-litre Ford Zeta engine, the Focus RS rated at 212 horsepower (158 kW). It would generate a steady 0.98G in lateral acceleration due to racing parts such as Sachs dampers, lightweight O.Z Alloy Wheels and a Quaife ATB Differential. It would also allow 1.0G of braking force due to the standard Brembo braking system 324 mm (Front) 280 mm (Rear). The development of the Focus RS was undertaken by a mixed team of mainstream Ford engineers (not SVE nor the TeamRS group which replaced it later on) and Tickford Engineering in Milton Keynes, United Kingdom. Originally it was to be released as the Racing Focus, however after the poor selling Racing Puma, Ford (driven by Martin Leach) decided to revive the RS badge. More bespoke than the concurrent Ford Focus SVT (badged as the Focus ST170 in Europe), the Focus RS upgraded or replaced 70% of the standard Focus mechanicals. The 1, 998 cc (2.0 L; 121.9 cu in) inline-four engine equipped with a single Garrett AiResearch GT25 (60) SG turbocharger produced a minimum of 215 PS (158 kW; 212 hp) at 5500 rpm and 310 N⋅m (229 lb⋅ft) of torque at 3500 rpm, [50] which was then mated to the 5-speed Ford MTX-75 transmission and not the Getrag used in the ST 170. Mechanically, most notably, the car incorporated a Quaife automatic torque biasing differential to improve traction from the front
