Timing an HEI distributor with vacuum advance?

Question

What is initial timing? Do I have to time this distributor with the vacuum advance plugged in and without out it once again? I've been trying to understand this statement,

"A good rule of thumb for a street/strip combo is about 14-18° BTDC initial advance to approx. 35° at 3000 RPM maximum advance".

Answer 1

There are two ways of advancing distributor timing.
Vacuum advance, and mechanical advance.
Your distributor has both.

Vacuum unplugged durring timing at idle

Answer 2

You time a car with vacuum advance off and plug the hose...this gives you initial timing for starting the vehicle...

As the throttle plates open, vacuum pulls the distributor to higher advance during acceleration...no, you don't time it a second time.

I've run up to 12 degrees advance on initial timing, but more would have your car bogging at high rpm, I believe.

Answer 3

If you have a dial back timing light just set the total timing at 38 degrees and forget it, you leave the vaccum advance plugged in doing it this way.