> Wouldn't the dwell by definition be 45 degrees (=1/2
> of a full cycle on one cylinder, or .5 x 360/4)?
No, the dwell is the degrees of rotation that the points "dwell" in the
closed position charging the coil. It could be done as you say, but there is
no benefit to the points staying open any length of time (the spark occurs
when the points open), whereas, as the rpm goes up, the length of actual
time that the points stay closed goes down and the ability to saturate the
coil is diminished, leading to a weaker spark at the top end where a good
racer needs it most. Thus the cam of the distributor is designed to maximize
the coil-charging time. In this case 60 dgrees closed, 30 degrees open.
david Lieb
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