Love them? Hate them? Do they dull the feeling of what the car is doing? Do they react poorly under certain loads? Or can you not live without the benefits? Whatever your personal opinion, there's a reason that vehicles today have one thing in common: power brakes.
Power brakes are not only safer for a street car, but they take less energy from the driver. If you aren't sure whether you've got power brake assist on your project car, take a look under the hood. There should be a brake booster on the driver side, and it should be connected to the master cylinder, which distributes brake fluid to each binder. An indicator of the absence of power brakes is a hard pedal feel, where you'll find yourself utilizing both feet to apply enough pressure to bring your street machine to a stop.
In a nutshell, the large round canister (brake booster) toward the rear of the engine that attaches itself to the inner firewall is a diaphragm. As a driver applies the brake pedal, the diaphragm uses vacuum from the engine and multiplies the pressure, distributing more force to the brakes with less effort from the driver. The theory is simple, and it works. Pedal feel may or may not diminish, but the benefit of more clamping force is a huge selling point for a lot of our 2-ton project vehicles.
Last month we showed you how to install a complete Pirate Jack's front cross-drilled setup on a '64 Nova wagon ("Drummin' Away"). While we could have squeezed in some info on the supplied power booster and master cylinder in the original story, we felt compelled to bring you a closer look as a completely separate install. The best part is that if you don't already have power-assisted brakes, adding them to your system won't take much effort. It's basically a straightforward remove-and-swap job.
We headed over to Reb's Specialites in Reseda, California, and got to work. Unlike the last time, we kept the jackstands in the garage and spent most of our time underneath the hood and dash to remove the manual master cylinder. It was only a matter of hours before we had power-assisted brakes and our feet could finally kick back and enjoy the ride.
What We Did
Installed a new booster and master cylinder assembly to our Pirate Jack disc brake setup
Apply the brakes with one foot now instead of two
We began by disconnecting...
We began by disconnecting the factory brake lines from the original master cylinder (non-assist). Under the dash we removed the pin that connects the master cylinder to the brake pedal arm via a rod.
To free the nuts holding the...
To free the nuts holding the master cylinder, we used a 9/16-inch wrench. We then removed the entire assembly from the firewall. The factory studs also needed to be taken out and were pushed through into the cabin. Use caution, as a cabin-side bracket may prevent the studs from sliding through easily.
Next we fitted the new Pirate...
Next we fitted the new Pirate Jack brake booster; however, we noticed that the firewall had been modified at some point with a thin steel plate riveted in place. Our new booster had three studs that needed to be slid through the firewall. Our factory setup only had two, so we had to remove the plate and drill an additional hole.