1977 140. revs slowly to 4000 rpm, then takes off

[bkache2]

trying to link and sync, have factory manual. Over the many years i've had to add little more turns to 'idle' screw to maintain 800rpm idle. This made cam wheel not line up with scribe mark anymore. It moved cam wheel over to "start" mark. I adjusted throttle yoke cam inward 4 turns which now put cam wheel at first scribe, like book says. Still accelerates slow to 4000, then takes off hard, as before. Starts great in 3-4 seconds every time. But my question is, there is also second scribe mark on curve piece of throttle cam.Is this the point where throttle should begin to open in relation to timing. My timing now does full advance before throttles move at all. When should throttles move in relation to full timing advnce. Plugs look light tan and temp is good ,110 compression .