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).

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.

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.

SOURCE
Master Power Brakes
254-1 Rolling Hills Rd.
Mooresville
NC  28117
704-664-8866
www.mpbrakes.com
Mancini Racing
Clinton Township
MI
8-00/-843-2821
manciniracing.com
Springs 'n Things
8-00/-903-9019
espo.com
Summit Racing
P.O. Box 909
Akron
OH  44309-0909
800-230-3030
www.summitracing.com
Firestone Tires
bridgestone-firestone.com
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