MASTER CYLINDER ADAPTER FOR CARS

Item No. AR058	Item No. AR059

Save weight and space by converting your musclecar over to the aluminum master cylinder. The late model master cylinder is smaller and much lighter than the original cast iron units. The late model aluminum master cylinders also exhibit excellent corrosion resistance which can help to keep the brake fluid clean.

AR Engineering offers two master cylinder adapters in order to match the most common configurations. AR059 has 4 studs which mount through the holes in the firewall. This style was used on many B body cars as well as early A bodies. AR059 has 4 holes in it for cars that have studs protruding from the firewall. The 1973 to 1976 A body cars use this style of master cylinder mount.

These adapters are designed to mate the later model aluminum master which started to appear in the 1978 model year and was gradually phased in. There are at least 3 different bore diameters used in RWD vehicles with the 1 1/32 diameter being the most popular. The light trucks used the same design but with a 1 1/8 diameter bore. Mopar Performance also sells complete aluminum master cylinders in two different bore sizes. We are partial to the unit used in the 1985 5th Avenue cars, but most any RWD master cylinder should work. Stay away from FWD car master cylinders. They look the same but many were designed for diagonal braking systems and may be calibrated wrong for your musclecar.

These master cylinder adapters are designed to be a direct bolt in replacement for your existing manual brake master cylinder. The thickness of the adapter compensates for the rearward placement of the piston in the aluminum master cylinder. This will allow your existing pushrod to fit without any further modifications. If you are converting from a power brake system then you may have other issues to solve. Some power brake cars used different pedal assemblies in order to reduce the amount of pressure applied to the brakes. The pushrod for the power brake assembly most likely will not work with the manual master cylinder and there may be issues with how the power booster was mounted to the firewall. In short, if you are converting a power brake car over to manual disc brakes you will most likely need to find other parts to complete the conversion.

Power brakes versus manual brakes: In our experience, there is no need to run power brakes in a musclecar era Mopar. If you have swapped over to the large 11.75 diameter rotors on the front then you will have enough brake torque without using a power booster. We recommend that the power booster be removed from any performance orientated vehicle and the car be converted to manual disc brakes using the aluminum master cylinder. This will provide you with plenty of braking power yet will weigh less and take up less room than the stock system. Manual disc brakes will also eliminate the need for engine vacuum to the power booster which in turn will allow a person to run a slightly hotter cam on the street. Chrysler engineers used manual disc brakes on vehicles as heavy as the D100 pickup truck so we are confident that this is a well engineered solution.