With only 209 units ever assembled, the South Africa-only E23 BMW 745i SA is surely a rarity and lesser known Bimmer. The story of the 7 Series luxury flagship began in 1977 with the E23 generation, which can be considered a successor to the E3 BMW New Six. The range-topping variant of the lineup was the turbocharged 745i, powered by the 3,205 cc M102 straight-six petrol unit. The M102 is the turbocharged version of the M30 engine generation.
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The European version of the BMW 745i (E23).
The 745i designation has a logical explanation. It came from the theoretical assumptions that a 3.2-liter turbocharge engine would have a similar output level as 4.5-liter naturally-aspirated powerplant. The multiplier in this case is 1.4 (45/32 = 1.4). However, the high-end 745i had a shortcoming. Due to the specific engine bay configuration, which took up a lot of space due to the additional turbocharger installed, the model was a no-go in right-hand drive markets.
The turbocharger was placed in the right side of the engine bay, as there was virtually no room to accommodate it on the left side due to the overall engine component configuration and the steering column.
For a RHD turbocharged 745i to exist, the steering column would have collided with the turbocharger on the right engine side, with no possibility to mirror the placement onto the left side of the bay due to lack of available space.
And now is the moment where South Africa goes into action. The BMW engineers at the plant in Rosslyn, in the northern part of Johannesburg, addressed the issue and decided to come up with an ingenious solution, which allegedly irritated the BMW management from Europe.
Their decision was to install the 3,453 cc, straight-six M88 powerplant originally developed for the M1 supercar. Specifically, South African engineers fitted 3.5-liter M88/3 engine to the range-topping E23 7 Series to create the special 745i SA. The 6-cylinder unit featured a cast iron block and an aluminum cylinder.
The high-revving M88/3 is a modified version of the original M88 unit for M1, which was also used to power the E28 M5 and E24 M635CSi. The naturally-aspirated powerplant developed a peak output of 210 kW / 286 PS (282 hp) at 6,500 rpm and a maximum torque of 340 Nm (251 lb-ft) at 4,500 rpm.
The M88/3 powerplant featured 24 valves (4 valves per cylinder) and replaced the Kugelfischer fuel injection system with the more modern Bosch Motronic solution. The compression ratio of the DOHC engine reached the value of 10.5:1, typically high due to the natural aspiration. The powerplant also displayed the M Power inscription on its cover.
With the help of the M88/3 under the bonnet, the 745i SA was capable of reaching a top speed of 236 km/h. The high-performance luxobarge also managed a decent 7.0 seconds from standstill to 100 km/h. Of course, due to the natural aspiration of its engine, the 745i SA was quite a noisy car, an aspect that would have been considered unworthy for a luxury limousine here in Europe.
Between 1983 and 1987, only 209 units of the 745i SA were ever produced at the BMW Rosslyn plant. Of these, 192 models were equipped with a 4-speed automatic gearbox, while only 17 were fitted with a manual, 5-speed Getrag transmission.
Besides the engine, the 745i SA also featured several technical enhancements, such as the M635CSi-sourced braking system and wider wheels compared to the European 745i model. In fact, the body of the South African 745i was also slightly wider as well. Last, but not least, as to give a hint on their powertrain and sporty valence, the 745i SA models displayed the ///M logo between the left, dual headlight set and the kidney grille.
Thus, even though BMW had and still seems to have a company policy of not offering a full-bred ///M 7 Series, the classic and unique 745i SA of the E23 generation can be truthfully considered to be the very first M7.
Most likely, very few (if not none) of the 209 units built could still be active today. Indeed, the 745i SA is yet another example of an unknown, rare and highly special BMW.