Electronic ignition upgrade

cuda66273 said
You're not limiting the top or the bottom..... you're limiting the total degrees of mechanical advance so your creating a window you set the bottom by turning the distributor, the top is the total amount of mechanical advance.

So if you want 2* initial and 20 total you would use the 18* slot, don't know of any engine that can run on 2*, most like 16-34 to we have that option in the plate being 0-10-12-14-16-18

The position of the slot effects the spring force resisting the weight. Within reason, further out acts more directly. This is a factor in how the curve is shaped. On hot rod, or desmogged vehicle, its more important to get the top - mid to high rpm shape. Besides, the initial can be adjusted with the spring perch.