History of the Porsche 924S
In 1984, VW decided to stop manufacturing the engine blocks used in the 2.0 L 924, leaving Porsche with a predicament. The 924 was considerably cheaper than its 944 stablemate, and dropping the model left Porsche without an affordable entry-level option. The decision was made to equip the narrower bodied 924 with a slightly detuned version of the 944's 163 bhp 2.5 litre straight four, upgrading the suspension and adding 5 lug wheels and 944 style brakes, but retaining the 924's early interior. The result was 1986's 148 bhp 924S. Porsche also decided to re-introduce the 924 to the American market with an initial price tag of under $20,000.
In 1988, the 924S' final year of production, power increased to 158 PS (116 kW; 156 bhp) matching that of the previous year's Le Mans spec cars and the base model 944 (itself detuned by 3 PS (2 kW; 3 bhp) for 1988). This was achieved using different pistons which raised the S' compression ratio from 9.7:1 to 10.2:1, the knock-on effect being an increase in the octane rating, up from 91 RON to 95. This made the 924S slightly faster than the base 944 due to its lighter weight and more aerodynamic body. The 1988 model also gained three point safety belts in the rear seats.
With unfavourable exchange rates in the late 1980s, Porsche decided to focus its efforts on its more upmarket models, dropping the 924S for 1989 and the base 944 later that same year.
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