Ok here is my deal. I own a 89 Foxbody Mustang. I have just replaced my master cylinder because it was going bad. I have installed a new Master Cylinder but the brake pedal is very stiff now. Upon applying the brake about an 1" the brake begins to engage. I have full stoping ability but it is hard to push. It isn't smooth or easy to push. I have done a quick google search and found nothing along with a quick search here on stangnet as well. I was hoping that maybe somebody could help me out on adjusting this problem. Just quick thought but could it be the "Pressure Differential Valve" or maybe the "Pushrod" is to far out?(Just taking a guess after doing some research) any help will be much appreciated.