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Bingo! Good job.
The vac advance dizzies are the -085 models, and are rarely found in U.S. market cars. I have an old, old B18 version on one motor, and a late European version on another.
It's likely you will have to tinker the advance curve for your particular motor no matter what distributor you put on it. What you're after is the maximum power at wide-open throttle across the entire rev range, with the vacuum disconnected. This is NOT the same as the most advance you can get without pinging -- too much advance will kill high-end power in many cases, even though it won't ping.
Vacuum advance has zero effect on WOT power. What it does is gives you additional advance in part-throttle conditions (less intake charge = less cylinder pressure = slower combustion = likes to be lit off earlier), which can significantly improve fuel economy. Without vac advance, it's running retarded in most real-life driving, which is why many people think they get better performance from using lots of basic timing.
Assuming your SUs don't have vacuum ports, you'll be hooking up to the full manifold vacuum. This will give you timing at idle in the 30 BTDC range with the vacuum connected, and the timing will actually back off a bit as the throttle is opened. Don't be alarmed at this -- it's just fine that way.
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