• madnificent
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    10 days ago

    Good point. They are called perfectly balanced engines indeed. There are tiny imperfections still. Although a V12 has less there still are some, mainly while revving. For all intents and purposes, the extra stability drowns in road imperfections.

    There may be more, but there’s a slight twist in the 2 L3 engines mated together in the connecting rods because they move from one side of the engine to the other and are not oerfectly opposed. The vertical motion is perfectly balanced but the distance they have creates a twist when it rotates from the left side of the engine . The V12 opposes that.

    The firing of the engine itself, front to back, may also contribute a minute amount of rocking which will make the L6 shake a tiny bit around its lateral axis.

    I have to think longer to figure out if the V angle made a difference aside from the obvious continuous time between firing in the cylinders. 60 degrees, 120 degrees and 180 degrees should all work? I don’t readily see what extra forces one balances out over the other so it’s likely a space and engine height challenge.

    I think what’s most noticeable is the increased amount of time pressure is being generated which also reduces the shaking effects because the engine rotates at a more constant speed.

    You can find the coin test where a coin is placed on the engine on its side and it doesn’t fall off due to vibration, even when revving the engine. I suppose that is moderate revving because the crankshaft still rotates in one direction which should cause a tiny bit of twist vs engine weight.