Power brakes are an amazing innovation and a vast improvement to the manual brakes on older vehicles. That doesn’t mean that classic vehicles are entirely left out, however. If you’re looking to improve your classic vehicle’s brake performance, shorten its stopping distance, and make braking easier on you as a driver, perhaps it’s time to look into power brake conversion.
What Are Power Brakes?
Power brakes use brake boosters to take the force you apply to your brake pedal and amplify it as it’s transferred to the brake master cylinder. From there, the rest of the brake system engages as normal. Power brakes significantly reduce the amount of force you need to place on the brake pedal when braking. There are three types of power brake boosters—vacuum, hydraulic, and electric, and they each amplify the force placed on the brake pedals in different ways.
Vacuum
Vacuum assist brakes are the original power brakes. These power brakes use a vacuum assist chamber near the brake pedal. The inside of the chamber is split into two sections with a moving metal plate between them. One section has a vacuum at all times created by the intake manifold. Depending on the brake pedal position, the second section is either at atmospheric pressure or has a vacuum.
A hole on the metal plate and a series of seals controls the amount of vacuum in the second section. When the brake pedal isn’t depressed, the seals remain closed and the vacuum in the first section creates a vacuum in the second section through the hole in the metal plate.
As the driver depresses the brake pedal, the seals simultaneously open to allow air into the section and seal off the hole in the metal plate. This creates a tremendous amount of force on the metal plate as air rushes into the vacuum of the second section. As the force pushes the metal plate, it in turn pushes on the brake master cylinder, which converts the force into hydraulic pressure on the brake fluid. The whole process makes engaging the brakes much easier.
Hydraulic
Hydraulic brake boosters operate similarly to vacuum assist brakes in that they increase the amount of pressure placed on the brake master cylinder whenever the driver hits the brakes. However, instead of using vacuum from the intake manifold, hydraulic power brakes use the hydraulic pressure from the power steering pump.
Electric
Electric power brakes are another type of brake boosters. These brake boosters use an electric pump and a booster system to create extra pressure on the brake master cylinder whenever the driver depresses the brake pedal. These power brakes are especially helpful for engines with low vacuum.
What Is Power Brake Conversion?
Power brake conversion is the process of converting a vehicle’s manual brakes into power brakes. It’s a popular procedure for classic vehicles, and it’s often done in tandem with other brake system improvements like converting drum brakes to disc brakes. Power brake conversion improves braking systems by making them easier to operate and improving stopping distance.
Power Brake Conversion Tips
Power brake conversion isn’t a procedure to be taken lightly. You need mechanic-level experience to safely execute the installation. If you plan on converting your manual brakes into power brakes, here are some handy tips.
Considerations
There are a couple of things to keep in mind when deciding whether to proceed with power brake conversion. For instance, installing a power brake booster will definitely help you increase pressure when stepping on the brakes, but if you don’t improve the brakes on the wheels themselves, it makes less of an impact on your vehicle’s braking efficiency.
Consider what type of power brakes you’ll need to install as well. If your engine doesn’t create enough vacuum pressure, you’ll need to use either a hydraulic or electric power brake system instead.
Also, you’ll need to account for pedal ratio when installing power brakes. Manual brake vehicles have a pedal ratio of 6:1, while power brake vehicles have a pedal ratio of 4:1. Pedal ratio has to do with the brake pedal’s pivot point and its distance from the middle of the footpad. As the first number in the ratio goes up, the brake force placed on the master cylinder also increases without the need for extra pressure on the pedal. However, it also necessitates more pedal travel when attempting to engage the brakes.
Do your research about what you need before purchasing anything. You can even ask a trusted mechanic what they would recommend. Sometimes, you might need extra brackets or other additional parts in addition to the kit. If you’re buying your power brake kit from a reputable place, they should give you all the needed information. They’ll also let you know if you need a new brake pedal assembly or just adjustments.
Parts and Kits
Power brake conversion kits come with most of the parts you need for the installation. Specialized kits are also available for specific vehicles. These kits are often the best fit for those vehicles, with calculations on pedal ratios and the like already accounted for. Power brake conversion kits will likely include a new brake pedal to address the reduced pedal ratio, brake fluid reservoirs, a proportioning valve to split the braking force between the front and rear wheels, and a brake force distribution block.
If you’re looking to create your own power brake kit for a vehicle without a pre-existing kit, then you’ll likely need to fabricate your own mounting points and bend new brake lines.
Installation
Installing your power brake conversion kit will take a good amount of time and effort. Remember to leave this step to a trusted mechanic if you aren’t too familiar with the braking system. You’ll often need to remove numerous parts before you can even begin. Access to the master cylinder is essential, and in a packed engine bay, it’ll take a lot of finagling. Don’t forget to disconnect the brake lines as well.
After that, it’s a matter of removing the old master cylinder and the brake pads. Once you install the new master cylinder, vacuum hose, brake pedal, and brake booster, you can reattach the brake lines and bleed the system to start completely fresh.
Modern vehicles all benefit from power brakes, and while installing one in your vintage car might take a good amount of time, effort, and money, it’s definitely worth it if you’re upgrading the entire system. Now that you know about what goes into power brake conversion, you can decide whether it’s worth doing.
Where to Get High-Quality Brake Products for Your Vehicle
Before considering power brake conversion, you should first ensure your car’s braking system is functioning properly. Replace parts that are damaged, worn out, or faulty. Head to CarParts.com and check out our catalog of braking system products.
Find what you need in a matter of minutes by entering your vehicle’s year, make, and model into our vehicle selector. This will narrow down the catalog to compatible products for your ride. For a more personalized shopping experience, use our search filters to find parts according to your preferred brand, price range, quantity, specs, and more.
You’ll never worry about going over budget when you shop from us. All our products come with low-price and lifetime replacement guarantees, helping you get the best value for your money.
Shop now, and get your order in as fast as two business days!
Keep Reading: Related Posts
Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.
