Trying to set timing but not sure what I'm doing. Read the shop manual--still not sure.
Start car, warm up, adjust idle to 850 RPM. Keep hoses to vacuum advance module attached. Adjust timing to 16 degrees BTDC. This causes an increase in idle speed. Readjust idle speed to 850 RPM. Under these conditions, I have 11" of vacuum on front of vacuum advance module when engine is revved up to 1500/2000 RPM. Have 15" of vacuum on the back side of the vacuum advance module at idle. Have 15" of vacuum at idle coming off the back side of intake manifold that feeds the HVAC/Cruise/Door locks. When I remove hoses to the vacuum advance module, the idle speed increases to 1200 RPM. and the timing goes to 25 degrees BTDC.
Is this what is supposed to happen?