Help with brakes PLEASE!

[sr nova boi]

Hi all, i have recently fitted astra gte 16v calipers and discs to my 1.4sr nova. Problem is now the pedal sinks to the floor and locks up on the passenger front wheel and feels really unstable under braking! i have bled the two front calipers and the rear passenger one, as the bleed nipple has sheared off the drivers side back drum. could this be whats causing it? Any help appreciated, cheers, rob

[mowgli]

at a guess, yes. get a new cylinder. it won't cost much. then adjust the rear brakes up, then bleed it right round a couple of times. then it should be good