Universal 7" Brake Booster and 1" Master Cylinder Kit for Early Hot Rods and Trucks: Frame-Mounted, Fits Auto Transmission, Dual Reservoir, 6:1 Pedal Ratio, Under Floor Power Brake Conversion

Learn more about selecting the proper master cylinder for your vehicle by reading our tech article, Brake System Selection. Universal bracket assembly converts under floor mount master cylinder applications to power brakes. Power brake pedal assembly mounts to inside of frame rail or boxing plate. Retains through the floor pedal for period looks while improving braking safety. For automatic transmission applications only. Pedal ratio is 6:1 for ease of braking and works with all disc/drum setups. Corvette style cast iron master cylinder provides line access from either side of unit and includes port plugs. Master cylinder utilizes 1-inch bore with dual reservoirs for additional brake system safety w/ 1/2"-20 & 9/16"-18 IFF outlets. Single diaphragm power brake boosters are compact and works with any engine providing at least 17 in/hg of vacuum.Power Brakes for Your Early Hot RodThere is no denying that early braking systems on the cars we love to build, like Model Ts, Model As, and other pre-war rides, were rudimentary to say the least, and that is putting it lightly. These early mechanical brake systems may have been OK for the speeds of the time, but drop a hopped-up Flattie in it, or even more power via a small-block Chevy, and you are really asking for trouble when you must hit the "whoa"pedal after using too much of the "go"pedal.Updating these classics to "juice"brakes (hydraulically actuated) has been the thing to do for decades and we are here to make that conversion easier for you. From disc and drum conversions, brake lines, proportioning valves, fittings, and more, Speedway Motors has everything you need to convert to hydraulic brakes on your pre-war hot rod, including this universal frame mount brake booster and master cylinder combo. These are the basis for your new hydraulically actuated braking system in your pre-war car and can easily be used to retain that period looking under floor master cylinder/pedal assemblies in '40s and '50s cars and trucks when under dash or engine compartment room prevents adding a power brake booster and relocating the master cylinder to the engine compartment firewall.A Power Brake Conversion That Fits Most Early Hot Rods and TrucksAdding power brakes to a pre-war hot rod is not always easy. Most of these original brake systems featured a mechanical brake system and early hydraulic conversions fitted the brake master cylinder under the floor, which did not always provide the correct leverage for optimal braking. Upgrading to power brakes using our universal brake booster and master cylinder with frame mount pedal assembly is a much better solution. The manual to power brake conversion retains the through the floor pedal assembly for period looks, but provides a solidly built mounting bracket, a compact power brake booster, and dual reservoir brake master cylinder that works with any open C-style or boxed frame member. The period look brake pedal passes through the floor and works with automatic transmission applications only. This kit works great in conjunction with a front disc brake upgrade as well.Our frame mounted power brake booster and master cylinder combo kit features a zinc-plated 7-inch single diaphragm power brake booster that is only 3-3/8-inch thick, allowing the brake booster and master cylinder combo to fit within your hot rod's frame with ease. The power brake system works with engine vacuum of at least 17 in/hg or can be paired with an electric vacuum pump for those with aggressive cam profiles that produce insufficient vacuum. The power brake booster assembly includes mounting hardware for the booster and the master cylinder that mounts to it. Additionally, the booster includes an adjustable master cylinder pushrod and threaded pedal rod with lock nut for pedal height adjustment