3-Series (E21, E30)Chat relating to the BMW 3-Series from 1975-1983 and 1984-1991 line. Specific models: BMW 315, BMW 316, BMW 318, BMW 318i, BMW 320/4, BMW 320i, BMW 320/6, BMW 323i, BMW 320i. E30 Family models include: BMW 325e, BMW 325i, BMW 325is, BMW 325ix.
The V12 isn't 2 m20's, it's V12 motor that is run like two 6 cyl with 4 ECUS, 1 for each 6 cycliners, 1 to control the two then a final one to basicly oversee them. Drive by wire control works the throtle. (No cables) The heads are totaly different from the M20, slender, they are run by timing chain. The heads interchange from left to right by swapping a plate. The Aluminum alloy in this engine has silicon mixed in and after machining the bores the aluminum is etched out to leave a crystallized silicon surface, the piston rings run on the aluminum cylinder bores (no sleeves). I have worked on a few V12's and I'm (in the not to distant future) putting one into an e30 bmw, I have done my homework. If you want to know anything else about the V12 just ask.
The valves are shorter, and are worked by a ball pin type hydraulic tappet, simular to a MB V8 cyl head, eclipse 2.0 cyl head, etc. (no adjusting) The lobes are also much wider than the M20's. and over all longer. Nothing interchanges between the M20 and the M70. Well may be the spark plugs do, um, nope they are different too.
You are looking at about 4500+ (parts only) for a conversion. Then you have to add labor for cutting, welding, rewireing, and cooling/suspension/drive train modificatons. And roughly 30+ work hours saying we have everything there and a solid car for a base to start with. Then about another week to find and fix bugs that may surface. Not easy or cheap, but very orginal and jaw dropping.
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