For your information I just posted my install of a 90 Chevy Caprice vacuum booster in place of the original booster and all I can say is it is night and day. I can now lock up the brakes!!! Whohoo!!!
http://turbobuick.com/forums/thread...ual-or-single-diaphragm-booster.370682/page-2
http://turbobuick.com/forums/thread...ual-or-single-diaphragm-booster.370682/page-2