How much cam, till vacuum drops to low
 

I've read of people running 230 to 240 degrees of duration @.050 and have yet heard anyone complain of vacuum loss. I realize I'm old school, but in my day, cams of that size would never work on a car with power brakes... What's the deal?

They still seem to produce enough vacuum with the need of a vacuum canister. Ive never put a gauge on mine, but ive never had a problem with my brakes.