Join Date: Sep 2000
Location: Washington, Michigan USA
You don't have 60 total - the vacuum advance doesn't operate at high load/low vacuum conditions, so you don't count it. "Total" is base timing (set with vacuum advance disconnected) plus whatever centrifugal is added by the distributor. 20 initial sounds pretty stout, and you say you're not getting any vacuum advance at idle with the distributor connected to the front port on the Holley? Is it the front port on the carb base, or the port near the top of the front metering block on the pass. side? The latter is "ported" vacuum, which provides no vacuum at all at idle, and the front port on the carb base should be full manifold vacuum at idle. I think you'll prefer manifold vacuum to the distributor for improved throttle response and smoother idle.
Your total advance at 34 degrees is right on the money, but with 20 degrees at idle, it sounds like your centrifugal is already starting to come in (too early). 12-14 degrees is more common.
'69 Z28 Fathom Green