What is enough vacuum for power brakes?

Without measuring ..there is no way to know exactly how much vac...but that cam screams about 8" at idle installed in its sweet spot.

Without measuring ..there is no way to know exactly how much vac...but that cam screams about 8" at idle installed in its sweet spot.

Went out and put a gauge on it and its showing 8" at idle like you said. 16 " at around 2000 RPM