The upper series E23 was the first 7-series from BMW. E23 The first came in May 1977 on the market and led to the successful 3.0 series (series E3) ab.

Also, the models of the 7-series have a three-numeric model name.

The leading "7" stands for the series. The two figures behind the "7" means one hundredth of the cylinder capacity in cm ³. There was, however, in some cases, a rounded-off in favor of the desired model number and is therefore not always mathematically correct. An exception is the 745i model, whose engine 3210 or 3430 cc has, however, with a turbocharger equipped. Here, the charge raised by this power by a selected number of higher expression. According to BMW's prospectus of 1980, the number 45 to the 7 by then in the usual formula for motorsport turbo vehicles identified (Capacity = 1.4 times the engine capacity class in the turbo cars were used). It was then at 3210 cc, the number 4494th The result was probably the designation 745i. Contemporary rumors said that the name of the then planned but, due to the Ölknappheit discarded Twelve-cylinder engine and was maintained.

The trailing "i" in the model designation indicates an engine with fuel injection ( "i" = abbreviation for Injection (engl. for injection)). Models without the appended "i" have a carburetor engine.