This seems high to me....
The vacuum gauge timing method is for people who just don't know any better.
Measure it with a micrometer
Mark it with chalk
Cut off with an ax
That's a rough equivalent of timing with a vacuum gauge. Use a delay-flash timing light and set the initial timing to 5-8 degrees BTDC. Then check the centrifugal and vacuum advance to be sure it's working smoothly and repeatably. The "listen for a ping and retard until it goes away" is a little better, but not a great deal. One degree of over-advance once the "sweet spot" for torque is found robs as much power as 5 degrees retarded from that point, so err on the side of "not enough" if you're unsure of where to set the timing.
Jerry
