I recently installed C5 brake calipers, Earl's brake bleeders, new brake hoses and flushed the brake fluid on my 85. I've bled the brakes 3 times and when the car is running if I leave the pedal alone for a couple seconds and then press it, it will go to the floor and the brake light will come on. Anyone have any suggestions or ideas?

There's a problem in the master cylinder. It could be worn out or there could be air in one chamber. The light's coming on because of this. If the 85 m/c's like most the switch to activate the light is a pressure differential switch, so when the pedal goes to the floor, the switch will activate. There may also be a low fluid switch which will be on the same electrical circuit but, probably not causing the light to come on.

You may have lost fluid in the m/c when you did the work. The m/c may need to be bled by it's self (bench bled). At least, I would try that before replacing it.

If your m/c has a lot of miles on it, it should be rebuilt or replaced anyway.

What Bill said, I would suspect the MC is leaking internally.

If I pressure bled the system at the master cylinder would that do the same as bench bleeding it? Bench bleeding a master cylinder is on thing I've never done on a car

That'll work. You can buy kits with plastic fittings for the front and rear circuits. You can get a full stroke on the bench though.

BTW, the 85 MC has two seperate front ports. Bastards.