[HWYSTR455]

It's easy to map your' existing advance curve with timing marks and a timing light. Just create a 2 axis chart on graph paper with timing on the left, vertical column have timing, from say 0-50 in 5 degree increments, and the bottom axis RPM from 0-6000 in 500 increments.

Hold the engine a each RPM point and read the timing with a light, and put a dot on the chart. Keep going until you have the lower axis completed, then connect the dots with a line.

This of course is done w the vacuum can plugged off.

Once done, at idle, you can use a hand vacuum pump on the vacuum can and slowly pump, going a half inch of vacuum at a time, and read the timing increase with the timing light.

EDIT: You can create a graph for that too, left vertical column do timing, and bottom column do inches.

Simple. No dizzy machine needed.


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