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Hello Clearwater,sorry for the delay,the question needed to be switched to the correct category,then my server crashed.
The distributor on these engines is a real source of confusion. If it has an odd-fire pattern that results in 45 and 75 degree spacing on the lobes around the distributor shaft, you would think the distributor cap has that same sort of spacing? No, not in this case. What the original engine designers did was take advantage of the fact that the contact point on the rotor can be made longer than normal. Draw a circle that follows the circumference of the rotor's outer contact, then draw a straight line from the center of the circle to one end of the rotor contact and another line to the other end. What you've just drawn is an angle of at least 15 degrees. Since the evenly spaced lobes on an odd-fire points type distributor cap are 60 degrees apart and the distributor shaft lobes are at 45 and 75 degrees, a little subtraction tells you that this will all work out. Simply put, 50% of the time ignition is taking place when the forward end of the rotor contact passes a distributor cap lobe, and the other 50% of the time ignition happens when the trailing end of the rotor contact passes a distributor cap lobe. Here are some pictures of the components.