1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 Mustang Hydroboost Braking. This kit is ideal for those applications that have little or no vacuum. The hydroboost uses the power brakes. Can adjust the amount of pressure coming from power steering pump. The kit is very small which makes mounting easy. The Hydro-Assist has a safety feature of a built in accumulator that enables you to stop the vehicle even though the engine may have stalled.