adding an intercooler, increasing compression to 8.5:1, lowering the suspension as well as various other little changes, Porsche was able to develop the 924 Turbo into the race car they had wanted, dubbing it the "924 Carrera GT". 406 examples (including prototypes) of the Carrera GT were built to qualify it for Group 4 racing requirements. Of the 400 roadgoing examples, 75 were made in right hand drive for the UK market. In 1981 Porsche released the limited production 924 Carrera GTS. 59 GTS models were built, all in left hand drive, with 15 of the 59 being race prepared Clubsport versions. Visually, the Carrera GT differed from the standard 924 Turbo in that it had polyurethane plastic front and rear flared guards, a polyurethane plastic front spoiler, a top mounted air scoop for the intercooler, a much larger rubber rear spoiler and a flush mounted front windscreen. It also featured Recaro seats with fine red pinstripes and body paint was available in black, "Guards Red" and "Diamond Silver". It featured Pirelli P6 tires as standard, and Pirelli P7 tires were available as an option along with a limited slip differential. It lost the 924 Turbo's NACA duct in the hood but retained the air intakes in the badge panel. This more aggressive styling was later used for as motivation for the 944. The later Carrera GTS differed stylistically from the GT with fixed headlamps under Perspex covers (instead of the GT's pop up units). GTS models were also lighter than their GT counterparts at , and Clubsport versions were even lighter at . In order to comply with the homologation regulations, the 924 Carrera GT and later 924 Carrera GTS were offered as road cars, producing 210 and 245 hp (157 and 183 kW) respectively. Clubsport versions of the GTS were also available with , and factory included Matter roll cage and race seats. 924 Carrera GT variations were known by model numbers 937 (left hand drive) and 938 (right hand drive). Carrera GTR The ultimate development of the 924 in its race trim was the 924 Carrera GTR race car, which produced from a highly modified version of the 2.0 L I4 used in all 924s, and weighed in at . This allowed for a 0–60 mph (97 km/h) time of 4.7 seconds and a top speed of . In 1980, Porsche entered three 924 GTRs at the