Posted by Chris Case [108.247.147.90] on Friday, December 04, 2015 at 13:42:24 :
In Reply to: never understood DWELL posted by DDD [209.253.157.5] on Friday, December 04, 2015 at 12:52:59 :
When the points are closed, the coil is building up it's magnetic field. When they open the filed collapses through the coils, making a high voltage surge. It is intensified because at the same time the condenser also discharges, sending higher surge back through the coil. 6 volts in, 20,000 out.
Dwell is "how long the rubbing block dwells on the cam lobe". Adjusted by changing the gap at the widest point.
Biggest problem is that rubbing blocks wear down with miles, and so the points do not open enough. Makes them hard to start. Too far open, and they are not closed long enough to saturate the coil with magnetism, so won't run at higher speeds.
"Dual pints distributors" used two sets of points, off set by umm 12 degrese. One opens, one closes, so the have longer dwell at high revs. By 12 degrees.
Unless I have it all bnackwrads. ;)
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