Do you know what's worse than texting and driving?... vacuum gauge + afr while driving!
Just now was my first time watching vacuum while driving. It is addictive.
This is a good observation Carl... although I'm using a torquey cam and big flywheel, the engine does bog easily when starting against such a ratio, especially uphill.
It seems like double pain when it bogs, manifold vacuum is reduced which takes the carb a while to react. If only it had a vacuum controlled accelerator pump like my toyota carb.
Here's some vacuum observations from a short drive just now:
Idling ~530 rpm = 16" vacuum, 12.5afr
Vacuum increases with idle rpm & choke ~17"
Vacuum goes up around 22" or more when engine braking... afr remains ~12
PP engages right around 5"... i had trimmed 4 coils from the spring, maybe that's why
Leanest AFR 16.5 to 17.5 occurs between 5 and 10" vacuum... light throttle
PP enriches it to 13.5 to 14.5 below 5" vacuum
Strangely it's a little richer ~4-5" vacuum but leans out to 14.5 at WOT
