Had to rebuild my 91 rear drums. New rotors, pads, and hardware. I also upgraded to 95 rotors/calipers, new booster and master cylinder. When the vehicle is jacked up and put it in drive I hit the brakes and the rears only slowly come to a stop, fronts stop immediately. the emergency brake keeps them solid so it must be a pressure issue? I have read about the LSPV so I removed it and tied it up as high as it would go, no difference. Thinking it is bad and should bypass it. I would still want a proportional valve there but what should I buy? Does anyone have a link?