BMW 5 Series (E12)

BMW 5-Series (E12)
Overview
Manufacturer	BMW
Production	1972–1981 699,094 built[1]
Assembly	West Germany South Africa[2]
Designer	Gruppo Bertone (concept) Paul Bracq (final design) Claus Luthe (facelift)
Body and chassis
Class	Executive car[3]
Body style	4-door sedan
Layout	FR layout
Powertrain
Engine	1.8-2.0 L M10 4-cyl 2.0-2.5 L M20 6-cyl 2.5-3.4 L M30 6-cyl
Transmission	4-speed manual 5-speed manual 3-speed automatic
Dimensions
Wheelbase	2,636 mm (103.8 in)
Length	4,620 mm (182 in) 4,826 mm (190.0 in) (US bumpers)
Width	1,690 mm (67 in)
Height	1,425 mm (56.1 in)
Curb weight	518: 1,240 kg (2,730 lb) 518: 1,250 kg (2,760 lb) (auto) 520: 1,310 kg (2,890 lb) 520: 1,330 kg (2,930 lb) (auto) 525: 1,350 kg (2,980 lb) 525: 1,370 kg (3,020 lb) (auto) 528: 1,385 kg (3,053 lb) 528: 1,405 kg (3,097 lb) (auto) 518i: 1,350 kg (2,980 lb) 520i: 1,350 kg (2,980 lb) 528i: 1,410 kg (3,110 lb) 528i: 1,430 kg (3,150 lb) (auto) 528i: 1,470 kg (3,240 lb) (US) 528i: 1,490 kg (3,280 lb) (US; auto) M535i: 1,430 kg (3,150 lb)
Chronology
Predecessor	New Class sedans
Successor	BMW 5 Series (E28)

The BMW E12 is an automobile made by BMW from 1972 to 1981. It was the first generation of the BMW 5 Series mid-size sedans. The E12 was released as the 520 and 520i 4-cylinder models, to replace the New Class sedans. A year later, the 525 with a straight-six engine was released and this was followed by 528, 530, 533, and 535 models.

The E12 M535i is considered to be the predecessor to the BMW M5.^[4][5]

The E12 was replaced by the E28 in 1981, although E12 production continued until 1984 in South Africa.

Styling

The 1970 BMW 2200ti Garmisch show car designed by the Bertone Design Centre set the style for the E12 5-series, with the final design by BMW's Paul Bracq.^[6][7]

BMW had previously located turn signal stalks on the right hand side of the steering wheels, and the E12 was their first model to have the stalk on the left side.

Models

The following models were produced in this series.^[8] All power and torque figures are manufacturer claims, measured according to the German Standard DIN 70020.

Model year changes

1974

• 518i model introduced

1975

• On the 520i model, Kugelfischer injection was replaced by Bosch K Jetronic.^[9]
• 528 model introduced

1976 facelift

With the introduction of the E23 7 Series, the E12 received facelift in September 1976. The rear-mounted gasoline filler door was relocated to the side of the car and the taillights were widened. The hood was redesigned to a give a 'power bulge' which accentuated the BMW kidney grille, and the dashboard ventilation was repositioned to improve air distribution.

pre-facelift (1972-1976)  post-facelift (1976−1981)  post-facelift (1976−1981)

1978

• The 528i model (using Bosch L-Jetronic fuel injection) replaces the 528 (which used two Solex Zenith 35/40 INAT carburettors)

1979

• 533i and M535i models introduced

Engines

M10 4-cylinder engine

Initially, the E12 used the 1.8 L and 2.0 L M10 four-cylinder engines (from the previous New Class sedans) were used for the 518 and 520 models. The 525, 528, 530, 530i and 533i models were fitted with M30 six-cylinder engines, as used on the large E3 sedans and E9 coupes.

With the exception of the 520i, four-cylinder and 2.0 L six-cylinder engines were fitted with Solex carburetors (although in the UK the four-cylinder 520 was fitted with twin Stromberg 175CDET carburettors). The 520i used the Kugelfischer mechanical fuel injection system from the BMW 2000tii and BMW 2002tii. Six-cylinder versions were available with dual Zenith two-barrel carburetors or Bosch L-jetronic fuel injection. Fuel-injected models carry the letter i at the end of their model designation.

The 1976 facelift saw the introduction of the 520 model, which used the 2.0 L M20 6-cylinder engine and replaced the 4-cylinder 520 and 520i models. This engine was initially named "M60", but renamed the M20 in mid-1981. The four-cylinder 2.0 continued to be used in South Africa, due to local content laws. Even after the M60 entered local production in 1979, the 2-litre M10 continued to be available with "518" badges in South Africa.^[10]

Besides the cosmetic facelifts, the 525 and 528's dual Zenith 35/40 INAT two-barrel carburettors were replaced with a single Solex 4A1 DVG four-barrel.^[11] The 528 was produced until September 1977, replaced by the fuel-injected 528i, beginning production in July 1978.^[12]

Drivetrain

The 4-speed manual transmission options consisted of:^[13]

• Getrag 242 4-speed (for M10/M20/M30 engine models)
• Getrag 262 4-speed (M30 engine)
• ZF S4-18/3 4-speed (M30 engine)

The 5-speed manual transmission options consisted of:

• Getrag 235 5-speed (M10 engine)
• Getrag 245 5-speed (M10/M20 engines)
• Getrag 265 5-speed (M30 engine)

The automatic transmission options- all 3-speed transmissions- consisted of:

• ZF 3HP12 (M10 engine)
• ZF 3HP20 (M30 engine)
• ZF 3HP22 (M20/M30 engines)
• BorgWarner BW65 (M30 engine)

Special models

E12 Interior

530/530i/533i/535i

Beginning in 1974 the Motorsport 530 or 530i "upgrades" were available strictly on special order for the 525/528 fitted with either the 3-liter 180 PS DIN engine from the BMW 3.0S or the fuel-injected 200 PS DIN engine from the 3.0Si. Other modifications were a rear axle ratio of 3.45:1 (3.25:1 for the 530i), a 25% LSD, vented disc brakes, Bilstein shocks, Scheel or Recaro sports seats, a sports steering wheel, light alloy wheels on lower profile tyres plus optional (often omitted) front-rear air-dams/spoilers.

Later, the similar Motorsport 533i and 535i packages were available for the 528i but featuring the 3.2L and 3.5L engines from the 633CSi and 635CSi. Finally the readily available "official" Motorsport version M535i, featuring a 3.5L engine with special styling such as Motorsport front and rear spoilers, Recaro-brand sport seats, a close-ratio transmission and limited-slip differential, larger brakes, and other styling cues such as Motorsport striping down the sides of the car and on the front air-dam plus the BMW M1 steering wheel was available between 1980 and 1981 with 1410 cars produced.

530 MLE

In South Africa, the 530 MLE was produced as a light-weight homologation special for racing (218 made in total).^[14][15]

Due to high import duties in South Africa, BMW sent E12 cars as complete knock down (CKD) kits to be assembled in South Africa for its own market. An E12/8 was built in the South Africa market just as the new E28 body replaced the E12 elsewhere. The E12/8 was essentially an E12 body fitted with the E28 suspension, electronics and interior.

North American-market models

Initially, only the fuel-injected six-cylinder 530i was sold in the USA. Changes for American-market E12s include lower compression pistons, larger bumpers (designed to withstand a 5 mph (8.0 km/h) collision with no body damage) and fender-mounted front turn signals. Emissions equipment such as EGR (Exhaust Gas Recirculation) and an air pump were used on the 530i, along with modified exhaust manifolds called Thermal Reactors.^[16]

The air-conditioning was not suitable for American temperatures. It is reported that, in an attempt to convince BMW that a more powerful air conditioner was needed, two BMW engineers were subjected to a long trip to Texas in the rear seat of a black BMW 530i with the power windows disabled.

For the 1979 model year, the 528i replaced the 530i. The new model featured several improvements for the American market: the Thermal Reactor and air pump system were replaced with a 3-way catalytic converter and the car's Bosch L-jetronic fuel injection system was now fitted with an Exhaust Gas Oxygen sensor. Power dropped marginally, and unlike the 530i, the car could no longer be operated on leaded gasoline.^[16] In the later years, North American-market E12s in the later years were generally sold as 'upscale' models and as such they were fitted with power windows, wood trim, and usually leather interiors and air conditioning as standard.

Critical reception

While being commended for its acceleration and build-quality, Modern Motor criticised the 1978 528i was for unpredictable handling and excessive body roll.^[17] Steering corrections during cornering meant the car's body "lurches back annoyingly and messily", in part due to the soft springing and hard damping combination. In comparison to the Jaguar XJ3.6 and Peugeot 604, the car was viewed as narrow and cramped in the rear and prone to wind noise.^[18]

Production

The production total for the E12 is 722,435 units,^[19] including 23,100 produced in South Africa.

References

External links

Wikimedia Commons has media related to BMW E12.

• Horrell, Paul, "Driving every generation of BMW 5 series; From a luminous 'E12' through to the latest 'G30', meet the 5 family. Time to pick a favourite", Top Gear, BBC Worldwide