Hydroboost braking systems
Reading through this post here and is all interesting.
Have not heard anyone here just going with the 15/16" bore master cylinders vs the stock 1" or 1 1/16" master cylinder bores with the manual brake setups.
The 15/16" bore masters give more pedal stroke and require less foot pressure to operate, giving you more stopping pressure at the wheels and more control while braking.
Successfully did this on a 69 B body manual drum/drum car. Huge improvement and better control. Before with stock it took a lot of foot pressure with a very short stroke, so the brakes were pretty jerky . . kind of on or off.
Others have stated that the 15/16" bore masters give it closer to the power brake feel.
I was very happy with this improved control, and all for just the price of the replacement master and bleeding the brakes.
The B bodies are heavier cars, so imagine this will work even better on the lighter A bodies.
Good Luck on your projects . . .