Well after enduring lousy brakes with one of the floor mounted systems i've finally had success.

I took the opportunity to overhaul the system and fit a new pushrod on one of the master cylinders as I had shortened it too much.

I dismantled each cylinder and cleared out the sediment, how does it ever get there when it's all new i'll never know.

I then altered the pipework to the front brakes cylinder to put the brake switch in a position close to the cylinder, this was then closely followed by a new 2lb residual pressure valve.

I then drained the system and filled with new fluid. After that I very carefully bled and re-bled the brakes. At one point a quick stomp on the brakes produced a large air bubble from one of the calipers.

Success, now a brake pedal that will lock the brakes without travelling three quarters of the way down. I have a nice solid pedal

I'm convinced the residual pressure valve has helped tremendously. A lot of the travel originally was in first making the pistons come back out after they retracted. I would recommend one of these to anyone who has the same problem.

Residual pressure valves are really bad move usually used to fudge either a brake calliper fault, calliper design problem or a calliper bracket problem.

Hmm, it was recommended by Rally Design.

With the cylinders floor mounted the wilwood 4 pot calipers are above the cylinders line, this was causing the fluid to return back and the pistons to retract. OK it was a small amount as the pads are new but added to the pedal travel.

The valve has just added the 2lb pressure which in practice means the pads just touch the discs. I can still turn the discs by hand.

Previously the pads could move a small amount.

Sounds like a good fix.

As you say with a floor mounted set up there is always the possibility the fluid will drain back enough to give you those symptoms.