What causes you to SUDDENLY, lose braking power? Porsche MC...

[oicdn]

What causes you to lose braking power SUDDENLY???

Situation:

Somebody jumped out in front of me, I slammed on the brakes, and it was braking hard as usual, then I feel a pedal bump/feedback for a second, then the pedal just goes to the floor.

I pull over a couple miles down the road onto some WHITE gas station pavement, and let the car sit for awhile...about 30 minutes, as the beach access we wanted to goto was accross from the gas station anyhow...the road is pretty much a two lane backroad, so braking it's how I went a couple miles with no brakes. It's just that, somebody jumped into the road...

No puddles. No wet looking wheels. Fluid resivoir still has all it's fluid. Only, there's no braking power. I pumped the pedal like 65 million times, including driving it down backroads...there's no fluids on anywhere still, and my resivoir is still full....

What could it be?

I'm guessing it could be the master cylinder out, considering there's no puddles anywhere, but don't those usually go out over time, not just in a one time incident like mine???

I have a 944T master cylinder, in my boxes with other Porsche brake parts, waiting for my Porsche conversion to actually be complete. What do I need to do to put it on? I was told that there's no brake switch on the 944T MC, so I'de need to get a brass T, and buy a generic brake switch (they have universal brake switches???), then just put it in there so my brake lights light up...is that all that's required???