Engines Exposed: Just How Far Has BMW's Beastly V12 Come?

For example, at lower speeds the camshaft will move so valves will open later in order to improve idling speeds. See? Complicated. It's still damn cool, though. In any case, let's get back to the engine being huge. It weighed almost 600 pounds and required two batteries. It had two of everything, as a matter of fact. There were two separate air intakes and two alternators, one to power a separate battery for passenger features like a fax machine or a wine cooler. No, that is not a joke. The S70B56 was the largest variant of BMW's M70 engine that saw many applications (including the 7 Series), most of the time fitted to an automatic gearbox and occasionally a six-speed manual. The 850CSi could hit 60 mph in six seconds.

The M70 engine came with a lot of technically advanced features, including hydraulic valve lifters, an aluminum/silicone alloy engine block, MAF sensors (new for the time), and electronic throttle control (instead of the more common cable). That covers one car, but let's be fair. The 850CSi is pretty old at this point. It's awesome how big and loud and obnoxious it is, and how much technology it had to offer, but let's see how much BMW's V12 has changed. The last time BMW used a V12 was in its 760Li from 2008-2015. It had a 6.0-liter twin-turbo V12 that made almost 550 horsepower. That's quite a bit more than the S70B56.

Let's go and see what this newer engine has to offer in terms of technology. The 2015 760Li used the N74B60, which is a twin-turbocharged version of the N73, so let's look at that instead. The N73 had DOHC and direct injection, both of which its predecessor lacked. It kept the VANOS system, and used a valve timing system where each cylinder had its own valve timing assembly. So, more valve technology and such was present, however the N74 (which as you remember is turbocharged) did not have that crazy individual by cylinder valve assembly. Somehow BMW took a step back. Perhaps with turbochargers the V12 finally got too complicated for new technology. Does that mean the V12 hit a brick wall?

Does this mean no more development? We'll see. In any case, this is a small sliver of V12 knowledge. More modern examples could include Lamborghini's V12s, but they started with V12s in the early 1960s. The new Huracan uses a V10, so Lamborghini may even be steering away from its original bread and butter. BMW 850CSi photo credit: Bimmerforums user Omega man 1969.