[39chevy]

Is there any difference between a complete Master Cylinder with Booster, that mounts on the firewall, vs one that mounts under the floor, if so what is the difference? In other words can I use the same MC/with booster in any location?

 

[Centerline]

You can use it in any location. However if you use it under the floor you will have to use residual valves to keep the brake fluid from gravity feeding back into the MC if it's mounted lower than the calipers or drum brake pistons.