Hello guys I'm having issues with my 76 turbo swap z. I upgraded my rear to disk brakes maxima/300zx and Toyota vented up front. I installed a zx brake master cylinder and wilwood proportioning valve. I kept the brake distribution block by the firewall. Easy enough or so I thought. Now when I get the car out on the road it will run good for 30 minutes or so until my brakes heat up, my brake pedal goes stiff and brake response takes a dump. Any input would be awesome.