BMW E23

BMW
BMW E23 (1977–1982)
7 Series (E23)
Sales designation:	7 series
Production period:	1977-1986
Class :	Upper class
Body versions :	limousine
Engines:	Petrol engines : 2.5-3.5 liters (110-185 kW)
Length:	4860 mm
Width:	1800 mm
Height:	1430 mm
Wheelbase :	2795 mm
Empty weight :	1530-1700 kg
Previous model	BMW E3
successor	BMW E32

The luxury class series BMW E23 was the first 7 series from BMW and came onto the market in spring 1977. It replaced the E3 series produced from 1968 . The French car designer Paul Bracq was responsible for the series, but he had to cut back on the design and left BMW in 1974.

After the 5- series from 1972, the 3-series from 1975 and the 6-series from 1976, the 7-series models were the provisional end of the reorganization of BMW's passenger car range at the end of the 1970s. All four series were now rearranged through model names and recurring design features. The successor to the E23 is the E32 built from autumn 1986 .

Model history

General

Rear view

At the market launch in May 1977, the 728, 730 and 733i models with the M30 engines taken from the previous E3 model were in the range. Formally, the 6 Series Coupé ( E24 ) presented at the beginning of 1976 anticipated many design features of the 7 Series BMW; the chassis of the coupé was based on that of the first 5-series E12 .

The anti-lock braking system (ABS), which Mercedes-Benz developed together with Bosch , was introduced in the E23 in 1979 . In September 1979, all engines were also equipped with the L-Jetronic electronic intake manifold injection from Bosch. The BMW 728i replaced the 728 and 730 models . The 732i with digital engine electronics (Bosch Motronic ) replaced the 733i. The BMW 735i has been added to the vehicle range. The BMW 725i was also launched . In Germany this was only offered to authorities and exported.

The top model, the 745i , came onto the market in April 1980 with the 3.2-liter engine known from the 732i , which achieved an output of 185 kW through the use of a turbocharger and an intercooler . Three years later, the engine of the 735i served as the basis for the 745i , which did not change the power, but only brought more torque.

Facelift

With the introduction of the 728i / 732i at the end of 1979, the rotary controls for heating and ventilation on the dashboard were redesigned. The air distribution was realized by pneumatic buttons and the analog clock was replaced by a digital one. This created space for the optionally available on-board computer. In August 1982 there was a major model maintenance measure . In addition to other vehicle changes - the front was aerodynamically redesigned - the 745i model was equipped with the turbocharged engine of the 735i . The engine performance did not change, but the response and the pulling power were increased.

From 1984 the 735i was available with a catalytic converter , until January 1985 only in conjunction with an automatic transmission. From October 1984 to August 1986, 1237 units were delivered. From January 1985 to August 1986 738 units with manual transmission were delivered.

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  BMW 7 Series (1983–1986)

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  E23 USA (1983–1986)

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  E23 USA (1983–1986), rear view

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  BMW 745i, view into the cockpit with the airbag steering wheel

Model names

The models in the 7 series also have a three-digit, numerical model name.

The preceding "7" stands for the series. The two digits after the “7” are the abbreviation for the displacement . In some cases, however, there was a rounding up or down in favor of the desired model name and is therefore not always mathematically correct. An exception is the 745 i with a turbocharger and intercooler , which had an engine derived from the BMW 732, initially with a displacement of 3210 cc. In an advertising-effective way, the higher engine power should be expressed by a higher number. According to the BMW prospectus from 1980, this was determined by multiplying 32 by the formula for turbo vehicles commonly used in motorsport at the time (cubic capacity times 1.4 = the cubic capacity class in which turbo vehicles were used). This then resulted in the number 4494 with a displacement of 3210 cm³ (→ 45). This is probably how the name 745 i. Contemporary rumors said that the name came from the twelve-cylinder engine planned at the time, but discarded due to the second oil crisis in 1979/80, and was retained. The model name 745 i was retained in 1983 when the displacement was increased to 3430 cm³.

The following “i” in the model name indicates an engine with intake manifold injection (“i” = abbreviation for Injection) . Models without a trailing "i" have a carburettor engine .

Export variants

In the UK was 745 i not available. With the right-hand drive there , the steering column on the right left no space for the turbocharger. Therefore there was a 735 tuned by Alpina exclusively for the British market .

In South Africa , BMW South Africa manufactured a model of the E23 in Rosslyn near Pretoria from 1983 with the internally M88 / 3 engine from the M635 CSi , in the E23 the output was 213 kW (290 hp). The engine torque was 340 Nm at 4400 rpm. This vehicle was called the BMW M745i and 192 units were built until 1985. At the time, this vehicle was the fastest BMW 7 Series in the world.

Only the 733 i and 735 i versions were available in the USA . From 1985 the model range was expanded with the L7. This was a luxurious version of the 735 i, which was intended exclusively for the American market. An important difference was the special leather interior, in which the dashboard and door panels were also covered with leather. Many optional extras were built into this vehicle as standard. All L7 models have an automatic transmission .

Technical specifications

The BMW E23 was equipped exclusively with six-cylinder in - line engines of the M30 type and in exceptional cases with the M88 / 3 sports engine based on the M30 . However, larger engines were also planned during development, some of which had already been tested in the predecessor. The development department found the eight-cylinder with four to five liters displacement to be too big and too heavy. A more modern twelve-cylinder - V engine was rejected out of concerns after the second oil crisis in 1979/80 offer a "too flashy car." Later they even tried out the 4.5 liter eight-cylinder from Porsche . The reason for this was that this machine was only built into the 928 at Porsche and there was only a small number of pieces. However, there was no collaboration, as BMW found that the Porsche V8 with 240 hp was hardly more powerful and less flexible than its own in-line six-cylinder.

Engine data up to 1979

model	Displacement	cylinder	power	Max. Torque	Compression ratio	construction time
BMW 728	2788 cc	6th	125 kW (170 hp) at 5800 min -1	238 Nm at 4000 min -1	9.0: 1	05 / 1977-08 / 1979
BMW 730	2985 cc	6th	135 kW (184 hp) at 5800 min -1	260 Nm at 3500 min -1	9.0: 1	05 / 1977-08 / 1979
BMW 733i	3205 cc	6th	145 kW (197 hp) at 5500 min -1	280 Nm at 4300 min -1	9.0: 1	05 / 1977-08 / 1979

Engine data from 1979

model	Displacement	cylinder	power	Max. Torque	Compression ratio	construction time
BMW 725i	2494 cc	6th	110 kW (150 hp) at 5500 min -1	215 Nm at 4000 min -1	9.6: 1	09 / 1979-08 / 1986
BMW 728i	2788 cc	6th	135 kW (184 hp) at 5800 min -1	240 Nm at 4200 min -1	9.3: 1	09 / 1979-08 / 1986
BMW 732i	3210 cc	6th	145 kW (197 hp) at 5500 min -1	285 Nm at 4300 min -1	10.0: 1	09 / 1979-08 / 1986
BMW 735i	3430 cc	6th	160 kW (218 hp) at 5200 min -1	310 Nm at 4000 min -1	10.0: 1	09 / 1979-08 / 1986
BMW 745i	3210 cc	6th	185 kW (252 hp) at 5200 min -1	380 Nm at 2600 min -1	7.0: 1	04 / 1980-08 / 1986
BMW 745i	3430 cc	6th	185 kW (252 hp) at 4900 min -1	380 Nm at 2200 min -1	8.0: 1	05 / 1983-08 / 1986

1. ↑ The BMW 725i was only produced for authorities that stipulated an upper limit of 150 hp for the procurement of company cars, as well as for export.
2. ↑ ^{a b} The BMW 745i is equipped with a turbocharger . The engine size multiplied by the factor 1.4 (known from motorsport) results in the model name.

Performance

The data given for the performance refer to the models with manual transmission. Vehicles that are equipped with an automatic transmission offer slightly lower performance.

model	Top speed	Acceleration from 0 to 100 km / h	1 kilometer from a standstill
BMW 728 BMW 728i	192 km / h 201 km / h	10.0 seconds 9.5 seconds	30.6 seconds
BMW 730	200 km / h	9.5 seconds
BMW 732i	208 km / h	8.6 seconds	29.5 seconds
BMW 733i	212 km / h	9.0 seconds
BMW 735i	217 km / h	7.9 seconds	28.7 seconds
BMW 745i 3.2 BMW 745i 3.4	222 km / h 227 km / h	7.8 seconds 7.9 seconds	28.3 seconds 28.2 seconds

body

The BMW 7 Series is a sedan - limousine mm with a vehicle length of the 4860th The vehicle width is 1800 mm, the height 1430 mm.

The curb weight of the vehicle (information in brackets for the version with automatic transmission):

725i	728	728i	730	732i	733i	735i	745i
1460 kg	1470 kg (1485 kg)	1470 kg (1490 kg)	1530 kg (1545 kg)	1500 kg (1520 kg)	1530 kg (1545 kg)	1500 kg (1520 kg)	(1590 kg)

Production numbers

The BMW 7 series was produced from May 1977 to August 1986 in the following numbers:

725i	728	728i	730	732i	733i	735i	745i
921 pieces	30,717 pieces	62,908 pieces	16,848 pieces	54,776 pieces	27,238 pieces	60,746 pieces	16,031 pieces

In total over 270,000 E23, compared to the predecessor E3 with the same construction time an increase of around 50%.

swell

• Automobil Revue , catalog numbers 1977, 1979
• Hanns-Peter Rosellen: The white-blue miracle. BMW history and types. Seewald Verlag, Stuttgart 1983, ISBN 3-512-00650-7 .

Web links

Commons : BMW E23  - collection of pictures, videos and audio files

• www.focus.de on Monday, January 16, 2017, 2:53 p.m.: Tradition 40 Years of the BMW 7 Series , accessed July 1, 2017.

Individual evidence

1. ↑ Wert names German operating instructions 728/730 / 733i, 25.VIII.78 3rd edition (order number 01 409 599 540), technical data page 124.
2. ↑ faz.net of October 14, 2012, masterpieces for 500 marks , accessed on March 11, 2020.
3. ↑ Paul Bracq's career timeline (web archive) , accessed on March 15, 2020.
4. ↑ The South African E23 M745i .
5. ^ Heinz-Peter Schmitz: Details BMW 745i South Africa version (January 28, 2007) ; available July 2, 2017.