1985 honda prelude si 5 speed 4 cylinder HELP!

[eddy_1988]

ok so i have a 1985 prelude si 5 speed 4 cylinder, and i have a problem i replaced my brakes and all that jazz and bled the brakes, but here the thing (all while car is running) when i press down the brake theres no pressure and car rpms drop and almost stall i rev up and pump brake a few times little pressure builds up but rpms drop again and have to rev up i stop pressing brake rpms are fine but no brake pressure. i cant see any leaks at any cylinders or in the lines any answers people help me out? also whats a good engine swap for this car