Non-Power Disc Brakes . . .
Plenty of cars were built with non-power disc brakes. From ‘57-‘61 the Citroen ID19 sedan had non-power front disc brakes as standard equipment. The brake calipers themselves were the same as the more posh DS19 introduced in the fall of ‘55, but the DS always had power brakes. For ‘62 the ID was upgraded to power brakes as well, albeit with a somewhat different system. Presumably this was because some felt the non-power ID system took too much effort but it was also likely driven by the desire to get brakes that automatically proportion themselves front to rear according to the load in the car. These power systems are true power brakes, not power assist in that they have no master cylinder or vacuum booster but are operated by an engine driven high pressure hydraulic circuit so the pedal only opens the proportioning valve. The D series cars were always fitted with radial tires right from the beginning of production.
To my knowledge GM’s first disc brakes on an American car come on the ‘65 Corvette. They are on all four wheels - the ‘Vette never had a split front disc/rear drum system - and power assist was an option not all cars had. I’ve put plenty of miles on a ‘66 without power assist and liked the brakes; the car stopped well with good feel and moderate effort. Another car I’ve driven extensively with four wheel discs and no power assist is the Fiat X1/9. None of these ever had power brakes, even the last cars built in ‘88. Like the Corvette, it’s a very good system that IMO would not be improved by a vacuum booster.
There were other cars built with non-power disc brakes but I’m familiar with all of these.
Plenty of cars were built with non-power disc brakes. From ‘57-‘61 the Citroen ID19 sedan had non-power front disc brakes as standard equipment. The brake calipers themselves were the same as the more posh DS19 introduced in the fall of ‘55, but the DS always had power brakes. For ‘62 the ID was upgraded to power brakes as well, albeit with a somewhat different system. Presumably this was because some felt the non-power ID system took too much effort but it was also likely driven by the desire to get brakes that automatically proportion themselves front to rear according to the load in the car. These power systems are true power brakes, not power assist in that they have no master cylinder or vacuum booster but are operated by an engine driven high pressure hydraulic circuit so the pedal only opens the proportioning valve. The D series cars were always fitted with radial tires right from the beginning of production.
To my knowledge GM’s first disc brakes on an American car come on the ‘65 Corvette. They are on all four wheels - the ‘Vette never had a split front disc/rear drum system - and power assist was an option not all cars had. I’ve put plenty of miles on a ‘66 without power assist and liked the brakes; the car stopped well with good feel and moderate effort. Another car I’ve driven extensively with four wheel discs and no power assist is the Fiat X1/9. None of these ever had power brakes, even the last cars built in ‘88. Like the Corvette, it’s a very good system that IMO would not be improved by a vacuum booster.
There were other cars built with non-power disc brakes but I’m familiar with all of these.