BMW M3

The BMW M3 is a high performance BMW M GmbH version of the popular BMW 3-Series compact automobile. M3 models have been derived from the E30, E36, E46 and E90/E92/E93 3-series. Common upgrades over the "standard" 3-Series automobiles include more powerful and responsive (yet at times smaller) engines, improved handling/suspension, more aggressive aerodynamics/body, and multiple interior/exterior accents with the "M"/Motorsport nomenclature.

E30 M3

Based on the 1986 model year E30 3-Series, the first M3 was introduced with a 2.3L I4 S14B23 engine (or S14 in shorthand). The engine design was based on various BMW genealogy; 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 BMWs M1 and later M6 inline-6 cylinder was adopted for aggressive breathing, resulting in outstanding performance for the day.

The most notable characteristic of the E30 M3 (relative to later M3 iterations) is its racing pedigree. It was campaigned by BMW as well as other racing teams including Prodrive and AC Schnitzer competing in many forms of racing including but not limited to Rally, DTM, Australian touring car and other series.

One of the main reasons for production of the road car was to homologate the M3 for Group A Touring Car racing. One of the reasons often cited for its creation was that it was to compete with the "2.3-16V"-model of the Mercedes-Benz W201 190E which was introduced in 1983, although this was only speculative. When the E30 M3 was in its final years of top level competition, the 2.5liter S14 engine in full race trim was capable of 340hp (250kW) plus, naturally aspirated.

The E30 M3 road car

The first road-going version produced 195hp (143 kW) (catalyzed model). Evolution models (not sold in North America) continued with 2.3liters but adopted revised exhaust-cam timing, increased compression along with the lack of a catalyst producing approximately 215hp (160kW). Later the Sport Evolution model production run of 600 (sometimes referred as Evolution III) increased engine displacement to 2.5L and produced 238hp (175 kW). 786 cabriolets were also produced, all by hand in BMW's Garching plant; at the time the 215hp (160kW) example was the world's fastest four-seat convertible.