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Part 7: Whoa There, Son-Valiant Gets New BrakesWe replace the rusted original front brakes on our Project Valiant with new stoppers. From the February, 2003 issue of Mopar Muscle By Randy Bolig Photography by Randy Bolig
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There was no way I trusted... There was no way I trusted the safety of my family with the rustedoriginal braking system. It may have been adequate when it was new, butthat was also when it had the 170-cid six-cylinder in it. Since the purpose of our project car, Valiant Effort, is to be a daily driver, we decided that in the interest of safety, she should be treated to a good set of disc brakes up front. Disc brakes weren't available on Valiants in 1967, and they didn't have the 5-on-4 1/2-inch bolt pattern to match the Rallye wheels given to us by a friend (thanks Ron). After the car is supported... After the car is supported by jack stands and the wheels are removed,you must release the tension on the torsion bars. Back out the bolt thatsticks down between the walls of the lower control arm. When introduced, drum brakes were an almost-sufficient way of stopping a vehicle. But, as cars became heavier and capable of higher speeds, halting that moving mass with drum brakes became more problematic. The difficulty with drum brakes is they tend to "fade" after prolonged use, as in traveling down a long grade or stopping instantaneously, for example. Early types of disc brakes (e.g., Kelsey Hayes) were better than drum brakes--cutting-edge braking technology in their time. Next, remove the brake assembly... Next, remove the brake assembly by taking out the cotter pins in theupper and lower ball joints, as well as the outer tie-rod end. Thenremove the nuts. We were also planning to replace the brake lines, so wejust cut the old, rusted steel lines. Cutting the lines was easier thanit should have been, so we're glad we planned to change them. However, in 1973, Chrysler went to the bigger 5-on-4 1/2-inch bolt pattern for their wheel mountings, and since the Valiant now sports the bigger bolt pattern in the rear, the same pattern in front makes sense. We want to avoid the necessity of two spare tires don't we? While finding a disc-brake setup off of a Duster or Dart may have been possible, a used assembly would have unfortunately cost $200 or more. Factor in the cost of new rotors, calipers, and ball joints (you would change them, right?) and your cost is close to that of a new aftermarket kit. Keep in mind while performing this conversion that the spindle on a disc- brake car is bigger, so you can't just slide a disc rotor over the drum spindle. Let's not even mention where you mount the caliper. Also, the ball joints on pre-'73 cars were smaller than the post-'72 units. The hole for mounting the upper ball in the A-arm is actually larger in post-'72 cars, and therefore, requires a change in the upper control arm and lower ball joint. We decided to call Master Power Brakes of Mooresville, North Carolina, and see how easy it is to change from drum brakes to disc. The kit arrived in three boxes with all the necessary components, minus the lower ball joints. The instructions say to re-use the old steering arm/lower ball-joint assembly, but the bolt holes are farther apart on the post-'73 models, and the old steering arm/lower ball joint physically will not bolt up to the new disc-brake spindle. Thankfully, a phone call to Just Suspensions of Fairfield, New Jersey, had us working again.  Removing the upper control...  Removing the upper control arms can be a real pain in the neck. Thecaster/camber adjusting bolts (arrow) usually rust to the steel sleeveinside of the control-arm bushing. If you need to cut the bolts, don'tworry--replacements are available from companies like Just Suspension.  After we cleaned, primed,...  After we cleaned, primed, and gave the suspension mounting area a coatof primer and black paint, we installed the upper control arm. HINT:Before you install the caster/camber bolts, coat them with antiseize toprevent them from rusting again.  After we bolted the caliper...  After we bolted the caliper bracket to the spindle, we loosely installedthe assembly onto the upper control arm.  Here you can see the difference...  Here you can see the difference in the pre-'73 (lower) and the post-'72lower ball joints.  With the lower ball joint...  With the lower ball joint attached to the spindle, connect it to thelower control arm and install the new nuts and cotter pins. You willneed different nuts and bolts to mount the steering arm to the spindlebecause the drum pieces are smaller.  The supplied rotor already...  The supplied rotor already has the bearing races installed, but beforeyou install the bearings and seal, clean everything with brake cleaner.  After you have properly packed...  After you have properly packed the bearings and installed the innerseal, place the rotor over the spindle and tighten the nut to 90 in/lb.Then loosen it. Now tighten the nut just until there is no play in thebearing (the Chrysler Chassis service manual says tighten finger tight).When you have the nut appropriately tightened, install the tin nut cagebefore you install the cotter pin. Herein lies the problem: The nut cagefrom the drum-brake spindle is smaller than the one on the disk spindle.We happened to find two that fit in a bucket of miscellaneous items.  Next, slide the inner brake...  Next, slide the inner brake pad in place so it rests against the rotorand is supported by the caliper bracket. With the outer brake padinstalled in the caliper, slide the caliper over the rotor.  Mopar calipers are held in...  Mopar calipers are held in place with these spring clips. The largerpiece is installed first, followed by the smaller one. One bolt holdsboth clips to the caliper bracket.  For the installation of our...  For the installation of our new front brake lines, we contacted RightStuff Detailing of Columbus, Ohio, and acquired new brake lines.Tweaking the hard lines is required since this is a custom installation.  The new master cylinder from...  The new master cylinder from Master Power comes with a bracket to mount the supplied disk/drum equalizer block.  We wanted the install to have...  We wanted the install to have a nearly-stock appearance (it is hard to see in this picture), but we opted to mount the block on the framerail.  With the hard lines in place,...  With the hard lines in place, we attached the Master Power supplied rubber lines. Don't forget the brass washer on each side of the fitting at the caliper.  After you have tightened the...  After you have tightened the fitting where the hard and soft lines connect, insert the clip that holds it all in place.  To remove the old master cylinder...  To remove the old master cylinder from the firewall, unbolt the rod that goes from the pedal to the master cylinder. This feat does require a contortionist, so be prepared. Once you disconnect the rod, remove the four bolts that secure the master cylinder to the firewall.  After you have "bench bled"...  After you have "bench bled" the master cylinder, mount it to the firewall. Then install the Master Power-supplied adjustable brake-pedal cylinder rod.  Here you can see that the...  Here you can see that the master cylinder is mounted and the new brake line from the master cylinder to the equalizer block for the back brakes is in place. We also installed a Biondo Line-Lock from Summit and mounted that to the inner fender. This requires brake-line fabrication, but Summit also supplied one of their Line-Lock install kits, which has various lengths of steel line and an assortment of fittings.  When it was time to crank...  When it was time to crank up the torsion bars, we contacted Mancini Racing and upgraded from the original six-cylinder bars to the 340 resto units. For racing only, the smaller six-cylinder bars react quicker and aid in weight transfer. Our Valiant will see more street time, so a nicer ride was planned.  With all lines installed,...  With all lines installed, the only thing left to do was bleed the brakes and wire-in the Line-Loc.  The Master Power instructions...  The Master Power instructions say to use 15-inch wheels. We had a set of 14-inch Ralleys from an '80-something Aspen. These wheels (made for disc brakes) cleared just fine, so we mounted newly released Firestone Indy 500 tires and placed them on the car.  In wiring the Line-Loc, we...  In wiring the Line-Loc, we didn't want the switch mounted to the shifter or the steering wheel, so we hid a three-way toggle switch under the dash. From there, we placed the wire coming from the horn button on the middle prong of the toggle switch. The spliced wire from the horn to the horn button connected to an outside terminal of the toggle. The third prong on the toggle has the wire from the Line-Loc connected to it.  The other wire from the Line-Loc...  The other wire from the Line-Loc is connected to a fused wire running to a 12-volt source when the ignition switch is on. Under normal driving conditions, the toggle switch is placed in the "horn" position. While at the track, the switch is placed in the opposite position, and while doing your burn out, all you have to do is hold the horn button to activate the Line-Loc.  Since we were getting deep...  Since we were getting deep into the disc brakes and torsion bars up front, we thought it wise to replace the six-cylinder springs in the rear as well. We contacted Springs and Things in Danville, Pennsylvania, who supplied a new pair of six-leaf A-Body springs.  We wanted to eliminate some...  We wanted to eliminate some inherent softness of rubber bushings when we mounted the rear springs. We ordered a pair of steel-sleeved aluminum spring-eye bushings from Mancini Racing and new rear-spring shackles and bushings. The front rubber bushings supplied with the springs were pressed out, and the alumninum pieces from Mancini were pressed in place and ready for the mounting brackets.  The front mounting bracket...  The front mounting bracket needs to have the spring mounting hole enlarged to 5/8 inch from 3/8 inch for the new bolt.  With the rear now more strongly...  With the rear now more strongly supported, it was time for shocks (by the looks of the old shocks, it was "time" some time ago). Summit was again called, and a set of their adjustable units was put on all four corners.  Well, here it is, riding on...  Well, here it is, riding on a new suspension, tires, and a disc-brake set-up. Now there's only one thing left to do . . .
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