BMW E23

BMW 7-Series (E23)

Manufacturer	BMW
Production	1977 - 1986 285,029 built
Predecessor	BMW E3
Successor	BMW E32
Body style(s)	4 door saloon
Layout	FR layout
Engine(s)	2.5L−3.5L I-6
Transmission(s)	4 or 5 speed manual, 3 or 4 speed automatic
Wheelbase	2795 mm (110 in)
Length	4860 mm (191.3 in)
Width	1800 mm (70.9 in)
Height	1430 mm (56.3 in)
Curb weight	1530 kg (3373 lb)−1670 kg (3682 lb)
Designer	Paul Bracq

The BMW E23 is an automobile platform that was the basis for the first BMW 7 Series luxury car, produced by the German automaker BMW. Replacing the BMW E3 large sedan, the E23 was produced for ten years from 1977 to 1987 and was replaced by the BMW E32 7 Series in 1986.

Design and features

All E23 7 Series models (with the exception of the 745i) were built with the 12-valve type-M30 six-cylinder engine as used in the older E3 and E9 cars. Although most E23 engines were fuel-injected, two models (the 728 and 730) were available with a Solex four-barrel carburetor until 1979, when they were replaced by the fuel-injected 728i. Early fuel-injected models used the Bosch L-jetronic system while later models used the more advanced digital Bosch Motronic system.

The E23 7 series cars were very upscale and sophisticated for their time. They were the first BMWs fitted with service interval indicators, a 'check control' that alerted the driver to various system faults, and complex climate control systems. On-board computers and anti-lock braking system (ABS) were optional on early models but later became standard features. A variety of options included leather upholstery, several types of wood trim, power seats, seat heaters, and power windows and mirrors. Later models were fitted with a driver's air bag. Four-speed and five-speed manual gearboxes were available (depending on the year) and an automatic transmission was also available.

A minor styling update in 1983 affected the 'nose' of the car (the front 'kidney' grilles, valance/spoiler, bumpers etc) as well as the dashboard and instrument panels which received updates plus (in the UK) the 735i received the Motronic 3430 cc engine (replacing the 3453 cc) and rear suspension modifications as well as numerous other minor changes. In the US, 1984 saw the arrival of the optional 4 speed automatic transmission (replacing the 3 speed unit previously offered), upgraded wood trim above the glove compartment and on the ashtray (previously plastic in all US models), electrically adjustable power seats and larger Michelin TRX radials with special TRX wheels (later standard on all 1985-1987 735i/L7 models) on the 5 speed manual models.

Special models

The 745i was a special high-performance model offered in left-hand-drive European markets between 1979 and 1986. It was originally fitted with a specially-prepared 3.2 L type-M30 six cylinder engine and a turbocharger producing 10 psi of boost, BMW engine code M102. In 1984 the engine grew to 3.4 L, BMW engine code M106, produced 6 psi intake pressure, and produced the same power output as the M102. These cars were all built with automatic transmissions (although there is documentation supporting how the ECU was modified at the factory to work with Getrag 5 speeds), and could be ordered with exotic options such as heated front and rear power reclining seats, auto-on aux interior gasoline fired heaters, leather covered cellular telephones, front and rear seat heaters, rear-armrest radio control, water buffalo hide upholstery, and burl wood trim. The water buffalo interior model was the Executive trim option, while the High Line trim package offered ivory leather interior trim including a leather dash board, sun visors, headliner, and other leather bits not offered on the Executive.

A different 745i was built for the South Africa market, because the turbocharger on the European-market 745i could not be installed in right-hand-drive versions of the car due to space restrictions in the engine bay (in RHD configuration, the steering shaft occupied the space where the turbocharger/exhaust was located on LHD versions). This car was fitted with the 286 hp (213 kW) dual-camshaft 24-valve type-M88 /3 Motorsport engine (with a Bosch ML-Jetronic fuel injection system) as used in the M635i, and M5. 209 of these cars were built between 1984 and 1986, fitted with either an automatic transmission or a 5-speed 'sport' gearbox. Of the 209 cars built 192 were automatics and 17 were fitted with manual gearboxes.

BMW South Africa ran one of these 745i models in Class A of the South African Modified Saloon Car Championship, the only BMW-Sanctioned motor sport application in the history of BMW 7-series cars.

American-market models

Only the 733i, 735i, and L7 were offered in America. As usual, BMW sold only upscale versions in the American market, with leather upholstery, cruise control, wood trim, power windows, power sunroof, and other options as standard. These cars were fitted with larger bumpers (to comply with Federal standards), smaller sealed beam headlights, and various forms of emissions equipment that were not found on European-market cars. American-market engines used lower-compression pistons and thus were less powerful than European-market versions. Some features such as ABS were available on European models before they were fitted on American models. Many turbocharged 745i models made their way into America during the height of the grey market in the mid-1980s.

The L7 was a more luxurious version of the 735i for the American market only. It featured special leather upholstery with leather dashboard and door padding (rather than wood trim), a power glass Moonroof. and a variety of optional features as standard. All L7 models were built with automatic transmissions. The L7 was also the first BMW sold in North America with a driver's side airbag.

Models

The following models were produced in this series:

Model	Engine	Power				Torque			Built
		PS	kW	hp	at rpm	N·m	ft·lbf	at rpm
725‡	2494 cc I-6	150	110	150	5800	208	153	4000	1977−1979?
728	2788 cc I-6	170	130	170	5800	233	172	4000	1977−1979
728i	2788 cc I-6	184	135	181	5800	235	173	4200	1979−1986
730	2985 cc I-6	184	135	181	5800	255	188	3500	1977−1979
732i	3500 cc I-8	300	220	300	5500	420	310	4500	1979−1986
733i	3205 cc I-6	197	145	194	5500	279	206	4300	1977−1979
735i	3453 cc I-6	218	160	215	5200	304	224	4000	1979−1982
735i	3430 cc I-6	218	160	215	5200	304	224	4000	1982−1986
745i	3205 cc I-6	252	185	249	5200	374	276	2600	1980−1982
745i	3430 cc I-6	252	185	249	4900	374	276	2200	1983−1986
North America and Japan
733i	3210 cc I-6	179	132	177	5500	266	196	4000	MY 1978−1979
733i	3210 cc I-6	176	130	174	5200	255	188	4200	MY 1980−1981
733i	3210 cc I-6	184	135	181	6000	264	195	4000	MY 1982−1984
735i/L7	3430 cc I-6	185	136	182	5400	290	214	4000	MY 1985−1987, L7 1986–1987
South Africa
745i	3453 cc I-6	286	210	282	6500	340	250	4500	198?−198?
Note: ‡ For government agencies and on special order only