Speedy Auto > Car Tech > 4x4 > Transmission Drivetrain

High Zoot Braking For Jeeps - Jp Magazine

Verne Simons Senior Editor, Jp Photographers: Christian HazelTrenton McGee

Brakes are very important, and for more reasons than our recurring nightmare where we are hurtling down the road in a car with no brakes. Many Jeeps, old and new, could use a little help when it comes to stopping especially after the addition of larger, heavier, more aggressive tires and wheels. You can toss larger discs, calipers, and master cylinders at your Jeep but that won’t necessarily make your Jeep stop any faster. Most stock master cylinders can handle some increase in caliper and or wheel cylinder size, but there is a limit to what stock components can handle. Combining the proper components with respect to fluid volume, pressure, and brake size is what you and we need.

braking Even 1949 Cj 3a Braking Photo 43237812

When the brakes on our custom ’49 CJ-3A started acting funny, we quickly placed a call in to Wilwood Disc Brakes. The folks at Wilwood know a thing or two about high-performance stoppage and can provide almost all the components that you need to make your Jeep stop on a dime. Follow along as we update our brakes to get our old flattie stopping with the best again.

braking Even wilwood Master Cylider System Photo 43237815

Here we have most of the components we are gonna use to get our Jeep’s braking system back up to par and more. The slim 1-inch-bore Tandem Remote Master Cylinder (PN 260-7563) with remote reservoirs and hose is the heart of the system. We also got a knob-type proportioning valve (PN 260-11179). Once installed, our system will be filled with Wilwood Hi-Temp 570 Racing Brake Fluid (PN 290-0632 for one 12oz can). We used about three 12oz bottles. Also note the red 10-lb residual pressure valve (PN 260-3279) we’ll talk more about that in a bit. PhotosView Slideshow

Here is a close up on the Knob-Type Proportioning valve. This valve has ports for front and rear lines in from the master cylinder, two front outputs, one for the front right, and one for the left, one output for the rear brakes, and a pressure switch for the brake lights. The knob can be used to adjust the pressure to the rear brakes so they don’t lock up to early. We like to set the proportioning valve so that the rear brakes lock up just before the fronts in dirt or gravel.

Countless old Jeeps have the factory brake master cylinder mounted to the frame, and while that is not necessarily the ideal placement, many Jeep nuts want to keep the factory through-the-floor-pedals in place. Several years back we mounted a larger-than-stock master cylinder to the inside of our Willys’ driver-side framerail. Years of wheeling and driving the old Jeep caused the master cylinder to start acting funny. We made this bracket out of some 3⁄16-inch plate. A little time with an 11⁄2-inch hole saw, a unibit, a chop saw, and our reliable Hobart 175 MIG welder will ensure the Wilwood master cylinder will now have a secure, flex-free, home in front of the brake pedal on the framerail.

The Wilwood 1-inch-bore tandem master cylinder with remote reservoirs comes with internal residual pressure valves for drum brakes in both the front and rear outlets. Per the instructions, we removed this spring and rubber seal from the front circuit, which is where we’ll hook up our disc brakes. Like most systems, the rear-most output on the master cylinder is for the front brakes. When sizing the bore of a master cylinder there are several things to take in to account; drums, discs, vacuum boost and so on. The easiest thing to do is to call the folks at Wilwood Tech and Sales support to help you figure out what bore size you need when ordering a master cylinder.

Getting back to the residual pressure valves we showed you earlier, they are used in-line on a Jeep when the master cylinder you are using does not have a metering block. The red 10-lb valve is used for drum brakes and holds pressure on the wheel cylinder so the shoes won’t back off the drums. Without this part in your system you may have to pump the brakes once to get the shoes out to the drums. The 2-lb valve (top, PN260-3278) is used in systems with disc brakes when the master cylinder is mounted near or below the same vertical height as the calipers. This keeps fluid from flowing backwards within the system.

Our 49’ CJ-3A runs a narrowed Dodge Dana 44 with six-lug Chevy 10-bolt spindles, hubs, and rotors to match our offset rear Cherokee Chief axle. The front brakes use the same calipers as many solid axle’72-’91 1⁄2-ton 4WD Chevys, some 4WD Dodges, and ’74-’91 fullsize Jeeps. Tossing a set of remanufactured calipers and pads is cheap and easy. The calipers were under $18 each (PN 18-4046 A1 Cardone) with a core charge and the pads ran $28.99 (premium) for all four from our local parts store. We’ve had old calipers grab and not fully release from internal rust build-up before, luckily replacements are available at almost any part store around the country.

We chose to mount the remote reservoirs on the firewall of our flatfender. This allows us to keep an eye on the level of the front and rear braking systems and allows for easy filling. We also added some small hose clamps on the lines running from the reservoirs to the master cylinder to prevent any leaks where the hose meets plastic.

Other Jeep Braking Tips and Tricks

PhotosView Slideshow

This picture shows the internals of the stock TJ/XJ proportioning valve. We’ve pulled the bleeder screw which holds that spring and plunger in place. If you add disc brakes to the rear of your rig and want a quick and easy way to get a little more fluid to those rear brakes pull your metering block apart and remove the little black rubber O-ring. You can do this mod with the proportioning valve in the Jeep—just work fast and put lots of rags under the valve, as brake fluid will run out. Take too long and your whole reservoir may drain out.

An old-school trick for running disc brakes on a rear axle of a Jeep and still retain a functional parking brakes is to dig up a set of ’76-’79 Cadillac El Dorado rear calipers (top). These calipers use the same mounting as Chevy 1⁄2-ton front calipers (bottom) so you can find weld-on plates to hold the calipers on almost any rear axle for a disc conversion. Another trick part to look for at the junkyard is Chevy/Dodge/FSJ caliper mounting brackets. These are used in front disc brake conversions on Dana 25s, 27s, and drum brake’d Dana 30s and 44s. You can also combine the Chevy backing plates, El Dorado calipers, and 11⁄8-inch ’80s CJ rotors on Dana 44s with a full-float kit. That means you can run 11-inch rotors and brakes on all four corners of an early CJ-5 or flattie.

Wilwood also sells other pedal kits that can be used in many configurations in your resto-mod Jeep project or even a dedicated Jeep-based rock or sand buggy. Here Editor Hazel modified an older Wilwood hanging pedal set for his very unique ’53 DJ-3A project. Wilwood sells hanging or floor-mounted pedal assemblies in dual (brake and clutch) and single flavor with both forward and reverse master cylinder placement.

Body Chassis Transmission Drivetrain Electrical Engine Suspension Brakes Wheels Tires Tech QA

High Zoot Braking For Jeeps - Jp Magazine

You Might Also Like

DON'T MISS