In fourteen years there are almost 100,000 engines.
A BMW 12-cylinder at that time was sensational, and not without risk. Nobody could have anticipated then, how many German 12-cylinders were still to follow the course of time after the second oil-price crisis. In terms of technology the challenges were not so big. Regarding the engine as a double 6-cylinder, there were, in principle, only the cylinder block and the crankshaft as fully new parts. Many components could be taken from the shelve. For example, the pistons were identical with those of the 1800.
However, the engine was developed from the largest of the small inline six cylinder, the 323 i, even if bore and stroke not so completely match. The mixture preparation (L-Jetronic) is used twice, inlet manifold with throttle valve part also. The toothed belt is not taken over because it would have to be much longer for a twelve-cylinder. There is a chain to tighten more easily and easier to handle also because of possible heat development.
Thus the transformation seems not yet have been quite so simple. And since one needs in any case a new engine block, one can also use aluminum immediately. Thereby the engine will slimmer down around and indeed does not get dry sump lubrication, but by a second pump is a reliable supply of oil and protect against unnecessary losses due to connection between the crankshaft and oil in the sump. The ignition system gets a fully electronic system, each with a ignition distributor per side. Sound and power delivery are naturally for that time something very special.
Staying with the changes. While until now the single camshaft has driven per cylinder head rocker levers, one changes now to towing levers because here's a chance to install in the pivot point a hydraulic valve clearance compensation. Counts not then to the moving masses. Logically, the future owners of twelve cylinders most likely to save the costs for the adjustment of valve clearance.