Production 1987–1996 Predecessor None | ||
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The BMW M70 is a V12 SOHC piston engine which was BMW's first production V12 and was produced from 1987 to 1996.
Contents
Design
The M70 was essentially derived from two M20 straight-6 engines joined at a 60 degree angle., however the two engines share very few cross compatible parts. The engine has the same bore and stroke on each bank as the M20, also the M70 has two Motronic ECUs (one for each cylinder bank). This said, the M70 engine does differ from the M20 engine in a number of key ways, including:
Some examples of this engine are fitted with two alternators, such as in the E32 750iL Highline. One alternator is a full sized unit to service the car as on "regular" V12 models (regular to be taken in context of course), while the secondary smaller unit is used to charge an auxiliary battery and power all options in the rear passenger compartment, such as telephones and fax machines, as well as the wine cooler, independent climate control and power sun shields.
The compression ratio is 8.8:1, stroke is 75 mm (3.0 in) and bore is 84 mm (3.3 in).
M70B50
Applications:
S70
The S70 was an enlarged version of the M70 fitted to the performance flagship models, as well as dedicated performance cars. There were two production generations
S70B56
This is a 5,576 cc (340 cu in) variant of the M70 engine. With 1,510 units produced, this is the lowest production BMW engine to date.
Applications:
S70/2
Among the improvements over the other M70/S70 engines, the S70/2 features 4 valves per cylinder and variable valve timing (called dual-VANOS by BMW). This engine is based on the European-market S50, and shares little in common with the rest of the M/S70 family.
Applications: