That is the type I am refering to. There are all kinds of boosters. Electric, hydrualic, etc. I am interested in the garden variety vacuum assist booster.
Here is a little cutaway drawing:
http://auto.howstuffworks.com/power-brake1.htm
I think the drawing in the link is misleading though. It has a caption that says "vacuum on both sides of the diaphragm". The darn thing wouldn't work unless there was a pressure difference.
You can answer one thing for me. Does my math seem to be correct and is my conversion from vacuum (inHG) to PSI correct?
Thanks
Rick