Tractor Police: What turns faster crankshaft or can shaft

My nephew was asked a question by one of the judge's today while judging his 1936 JD A,
Which turn's faster the crankshaft or the camshaft? He told them the camshaft.
I told my nephew I don't know but a good question.
So what is the correct answer?
 
The cam runs at half the speed of the crank. This is so the cam lobes only activate their respective valves on every other revolution of the crank.
 
FWIW I agree with Mike and Brendon, the cam only turn 1/2 the RPM as the crank. Its gear is twice the size/teeth as the crank gear which drives it.

John T
 
(quoted from post at 10:56:49 04/26/18) No. Police did not ask about the Mag.

Just wondered because of the rpms being considered unusual when everyone knows that in all ordinary applications that the cam turns at 1/2 speed.
The lettered and 1st numbered distributer rpm is uncommon and a curiosity
 

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