Let me initially say that I am nearly ignorant of modern engines. That
said...
As I was trying to fall asleep last night, I began to wonder why the crank
for my inline six (TR6) motor has all of the journals in the same plane (I
suppose you could argue that there are two planes though). Would it not be
more efficient (for multiple reasons, getting at them later) to create a
crank shaft with journals say within three difference planes, all separated
by 120 degrees?
Reasoning? Well last night I likened it to a water wheel. Obviously, a
water wheel with two "splash boards" is not going to be as efficient or as
powerful as one with more than two splash boards... until of course you hit
upon decreasing returns, but that is once you add lots of splash boards.
Anyway, for the purposes of relating this to a crank... a water wheel with
two splash boards will have a high rate of deceleration, and will be less
balanced than a water wheel with three or more splash boards, both of which
mean lost energy which we feel as less power.
Obviously the most notable change to the design of the motor, other than the
crankshaft, would be how you go about the timing. But I can't imagine that
to be too difficult.
Is there some reason why multi-plane cranks are not more popular (again,
like I said I know nothing about modern day motors)... ? Obviously, I am
not talking about motors with V blocks either.
Thanks,
Kai
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