BMW 3 Series (E21)

Definition
The BMW 3 Series (E21) is the first generation of BMW’s compact executive car series, produced from 1975 until 1983. Internally, it is designated by the chassis code “E21”.

Overview
Introduced as the successor to the BMW 02 series, the E21 marked BMW’s re‑entry into the compact luxury segment after a brief hiatus. It was initially offered as a two‑door sedan; a four‑door sedan variant was added in 1978. The model featured rear‑wheel drive, a conventional longitudinal engine layout, and a focus on sporty handling combined with upscale interior appointments. Production took place primarily at BMW’s Dingolfing plant in Germany, with a total output of approximately 1.3 million units worldwide. The E21 laid the foundation for the long‑running 3 Series lineage and established design cues that would influence subsequent generations.

Etymology/Origin
The “E” in BMW’s internal coding system stands for “Entwicklung” (German for “development”), and the number 21 denotes its sequential position within the company’s engineering projects. The public name “3 Series” follows BMW’s numeric series naming convention, indicating the vehicle’s placement in the brand’s hierarchy (with the 1 Series, 2 Series, etc., introduced later).

Characteristics

• Body Styles:

  • 2‑door sedan (1975–1983)
  • 4‑door sedan (introduced 1978)

• Dimensions (typical for the 2‑door version):

  • Length: ~4,300 mm
  • Width: ~1,635 mm
  • Height: ~1,380 mm
  • Wheelbase: 2,620 mm

• Chassis and Suspension:

  • Rear‑wheel‑drive layout with a longitudinally mounted engine.
  • Front suspension: MacPherson strut.
  • Rear suspension: Semi‑trailing arm.

• Engines (selected examples):

  • 1.6 L M10 inline‑four (118 hp) – 316 i
  • 1.8 L M10 inline‑four (130 hp) – 318 i
  • 2.0 L M10 inline‑four (125 hp) – 320 i
  • 2.0 L M20 inline‑four (115 hp) – 320 iS (sport‑tuned version)
  • 2.5 L M30 inline‑six (150 hp) – 325 i (introduced 1982)

• Transmission Options:

  • 4‑speed manual (standard on early models)
  • 5‑speed manual (offered from 1978)
  • 3‑speed automatic (optional, supplied by ZF)

• Interior Features:

  • Driver‑oriented cockpit with centrally mounted instrument cluster.
  • Optional leather upholstery, wood trim, and air‑conditioning in higher‑spec versions.

• Facelifts and Updates:

  • 1978: Introduction of the 4‑door sedan and minor exterior revisions (new grille design).
  • 1979: Launch of the “S” (Sport) models (e.g., 318 iS, 320 iS) featuring higher‑output engines, stiffer suspension, and sportier interior trim.
  • 1982: Introduction of the 325 i with the larger M30 six‑cylinder engine, representing the final performance‑oriented iteration of the E21.

Related Topics

• BMW 3 Series (overall) – The broader model line that succeeded the E21 with successive generations (E30, E36, etc.).
• BMW E30 – The second generation of the 3 Series, launched in 1982, which overlapped with the final year of E21 production.
• BMW 02 Series – The compact model series that preceded the E21.
• M10 Engine – The inline‑four engine family used in early E21 models.
• M30 Engine – The inline‑six engine introduced in later E21 versions and used extensively across BMW’s range in the 1970s and 1980s.

All information presented reflects widely documented specifications and historical records associated with the BMW 3 Series (E21).