how can i turn a joystick(fpr plane sim) into a handbrake?has anyone done this before???please help!

hi..ive just bought lfs and g25. how do i set my g25 wheel so it always matches the in game steering wheel. because at the moment even though i've set it to 900 it turns 270. im having real trouble because its too sensitive...please help i love the game but cant play it...if i move my steering wheel ever sooooooo slightly the in game steering wheel spins out...please help

please help its urgent...i cant oprn or save the car setup. what program do i need to have to be able to open the file?