There is difference or about 1/4" from the 7.5 degree notch when I static time vs. strobe light at idle. Which sould be more accurate of the baseline for tuning the carb? Engine has stock crank and pulley that came with the 73 AM motor.
I will try to borrow another light for comparison. BTW, I checked the timing with both a test light and volt meter to set the static and vacume lines were off and plugged to carb.