I am wondering, what is the benefit of the hydrovac system over just a regular master with proportioning valve? My 71 has the old hydrovac brake system, and it is kind of a PITA to deal with. The master is a single reservoir/single actuation, and if it were to fail, the system would not work at all. What I am getting at, would it be advantageous to convert to a single master with vac booster on the firewall like a light duty, or is the hydrovac actually stronger?

 

Pretty sure the hydrovac is stronger with bigger vacuum and fluid reserves. If you can get a bigger vacuum reserve dual master, you could try that, but you would have to balance it out and make sure you have enough fluid reserves as well. You probably have 2 wheel cylinders at each wheel, that adds up to a lot of fluid, and you need reserve fluid in case one poops out, which they are known to do.