Quote Originally Posted by aradralami View Post
why is there a required (with specified gauge) gap between the points in the contact breaker if it only needs to close the points in order to let current pass through? is there no need for current to make an arching?
The gap size, or "dwell" (time) is because it takes a certain amount of time to saturate the coil windings when the points are closed. This time is far from perfect with points because the time changes with the speed of the engine. It is a happy medium to make it run well at different rpms.