BMW 5 Series (E12)

BMW 5-Series (E12)
Overview
Manufacturer	BMW
Production	1972–1984 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 (181.9 in) 4,826 mm (190 in) (US bumpers)
Width	1,690 mm (66.5 in)
Height	1,425 mm (56.1 in)
Chronology
Predecessor	New Class sedans
Successor	BMW E28

The BMW E12 is an automobile which was produced 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^[6] designed by the Bertone Design Centre set the style for the E12 5-series, with the final design created by BMW designer Paul Bracq.^[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][9][10]

Model	Engine code	Power	Torque	Years
518	M10 (M118)	90 hp (67 kW) @5500	142 N·m (105 lb·ft) @3500	1974−1981
520	M10 (M17)	115 hp (86 kW) @5800	162 N·m (119 lb·ft) @3700	1972−1977
520i	M10 (M64)	125 hp (93 kW) @5800	177 N·m (131 lb·ft) @4500	1972−1975
		125 hp (93 kW) @5700	171 N·m (126 lb·ft) @4350	1975−1977
520/6	M20B20	90 kW (120 hp) @6000	160 N·m (120 lb·ft) @4000	1976−1981
525	M30B25	107 kW (143 hp) @6000	211 N·m (156 lb·ft) @4000	1973−1976
		110 kW (150 hp) @6000	211 N·m (156 lb·ft) @4000	1976−1981
528	M30B28	125 kW (168 hp) @5800	253 N·m (187 lbf·ft) @4000	1975-1976
		130 kW (170 hp) @5800	253 N·m (187 lb·ft) @4000	1976−1978
528i	M30B28	129 kW (173 hp) @5800	235 N·m (173 lbf·ft) @4300	1977−1978 (USA only)
		126 kW (169 hp) @5600	230 N·m (170 lbf·ft) @4500	1979−1981 USA only
		135 kW (181 hp) @5800	235 N·m (173 lbf·ft) @4200	1978−1981
530	M30B30	130 kW (170 hp) @5800	250 N·m (180 lb·ft) @3500	1975-1978 South Africa only
530i		131 kW (176 hp) @5500	251 N·m (185 lb·ft) @4500	1975-1978 USA only
530 MLE		147 kW (197 hp) @5800	251 N·m (185 lb·ft) @3500	1976 South Africa only
533i	M30B32	147 kW (197 hp) @5500	290 N·m (210 lb·ft) @4250	1979
M535i	M90	160 kW (210 hp) @5200	310 N·m (230 lb·ft) @4000	1979-1981

Model year changes

1974

• 518i model introduced

1975

• On the 520i model, Kugelfischer injection was replaced by Bosch K Jetronic.^[11]
• 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.^[12] The 528 was replaced by the fuel-injected 528i in September 1977. The facelift also resulted in the carburettor on the 525 and 528 being revised to a single four-barrel Solex 4A1 DVG.

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

The North American market E12 differed in several ways from the original German market versions. 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. The E12 5-series used a Behr air conditioner that was notorious for being too weak for American temperatures. A well-known legend is that, in an attempt to convince BMW that a better air conditioner was needed, two BMW engineers were treated to a long trip to Texas in the rear seat of a black BMW 530i with the power windows disabled.

BMW chose to sell only fuel-injected six-cylinder versions of the E12 in the North American market: the 530i and later the 528i. The American market imposed several restrictions such as bumper regulations, sealed-beam headlights, and emissions requirements. As such, American-market E12s were fitted with lower compression pistons, special 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. The latter caused several engine problems including burned exhaust valves and overheating, often resulting in warped or cracked cylinder heads. A separate defect in the 530i cylinder head design prompted a lawsuit against BMW. As a result, in 1980 BMW offered replacement cylinder heads for owners whose cylinder heads had cracked, even if the warranty on the car had expired. In 1979 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.

Critical reception

While commending for its acceleration and build-quality, the mid-70s 5-series was criticised for its "untidy" handling, being prone to sudden and sharp oversteer. Steering corrections during cornering meant the car´s body "lurches back annoyingly and messily",^[16] 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.^[16]

Production

The production total for the E12 is 722,435 units,^[17] including 23,100 produced in South Africa.

References

1. Oswald, Werner (2001). Deutsche Autos 1945-1990, Band 4 (1. ed.). Stuttgart: Motorbuch Verlag. ISBN 3-613-02131-5.
2. BMW South Africa, www.e12.de Retrieved 10 April 2016
3. "1980 BMW 528i specifications". www.automobile-catalog.com.
4. "Watch BMW look back at the M5's predecessor". www.autoweek.com.
5. "Welcome to the official 5 Series Register". www.bmwcarclubgb.uk.
6. "BMW - 2200 TI Garmish". www.allcarindex.com.
7. Norbye, Jan P. (1984). "Expanding on Excellence: The 5-Series and 3-Series". BMW - Bavaria's Driving Machines. Skokie, IL: Publications International. p. 209. ISBN 0-517-42464-9. Dimensionally, the 5-series differed only slightly from its New Class predecessors, but Paul Bracq's modern, stylish four-door body was far less boxy in appearance.
8. Werner Oswald: Deutsche Autos 1945-1990, vol. 4. Motorbuch Verlag, Stuttgart 2001, ISBN 3-613-02131-5, p. 226-231
9. Mike Covello: Standard Catalog of Imported Cars 1946-2002. Krause Publications, Iola 2002, ISBN 0-87341-605-8, p. 149-151.
10. Automobil Revue, catalogue edition 1979, p. 210.
11. "5' E12 520i FUEL INJECTION K-JETRONIC". www.realoem.com.
12. Haler, Justin, ed. (July 1979). "BMW's small six 520". SA Motor (Randburg, South Africa: SA Motor (Pty) Ltd) 17 (7): 26.
13. "5' E12 Model Selection". www.realoem.com.
14. "530 MLE E12". www.africanmusclecars.com. Retrieved 16 December 2013.
15. "BMW 530 MLE". www.e12.de.
16. Car Magazine, November 1975, page 60.
17. "Statistique de Production". www.e12.de.

External Links

• http://e12.de
• http://e12e28.de/index.php/en/section-e12-menu/section-e12