Based on the 1986 model year E30 3-Series, the first M3 was introduced with a 2.3 L I4 S14B23 engine (also known as S14). The engine design was based on various BMW parts: basic block layout from the M10 4 cylinder (found in the 2002 and 320 series) overbored and reinforced to similar specifications of the BMW M88 inline-6. The valve train and head architecture from BMW’s M1 and, later, M6 inline-6 cylinder was adopted for aggressive breathing.
In contrast to later M3 iterations, the E30 M3 was campaigned by BMW as well as other racing teams including Prodrive and AC Schnitzer competing in many forms of racing including rally as well as German, British, Italian, Belgian, French, and Australian touring. The production of the E30 road car was to homologate the M3 for Group A Touring Car racing. It was to compete with the “2.3-16V”-model of the Mercedes-Benz W201 190E that was introduced in 1983. In its final years of competition, the 2.5 liter S14 engine in full race trim was capable of over 250 hp (190 kW) naturally aspirated.
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| BMWE30 M3 |
The E30 M3 differed from the rest of the E30 line-up in many ways. The M3, although using the same basic unit-body shell as the standard E30, was equipped with 12 different and unique body panels for the purposes of improving aerodynamics, as well as “box flared” wheel-arches in the front and rear to accommodate a wider track with wider and taller wheels and tires. The only exterior body panels the standard model 3-series and the M3 shared were the hood, roof panel, and sunroof.
