There are lots of things to love about old trucks, they certainly have vintage charm and look cool, but underneath the sheetmetal is a chassis that’s just as vintage and not nearly as cool. Throw an old truck into a hard turn or slam on the brakes for a panic stop and a historic hauler will immediately demonstrate its shortcomings and the love affair will come to an end. And what good is a great-looking truck if you don’t love to drive it?
Jason Scudellari is the guy in charge of the Source Interlink Tech Center. Along with working on a variety of magazine projects, he’s putting together a 1956 Chevy pickup as a driver. To bring the truck’s ride and handling up to contemporary standards a new chassis from Fatman Fabrications replaced the original. To make sure the stopping power was commensurate with the newfound cornering capabilities, Wilwood disc brakes are being added to all four corners.
Wilwood was founded in 1977 and they have designed and manufactured brakes for all types of competitive motorsports, agricultural equipment, industrial applications, utility vehicles, snowmobiles, quads, motorcycles, military vehicles, and of course, trucks. They stock over 300 different brake calipers, 200 types of rotors, 100 master cylinder designs, and a wide assortment of brackets, fittings, valves, and brake lines. Off-the-shelf brake calipers range in size from those used on passenger vehicles to heavy-duty brakes for the U.S. military Humvee. In short, if you’ve got something that needs brakes, Wilwood has the parts to make it happen.
If you’ve ever rubbed your hands together on a cold day you’ve experienced a byproduct of friction—heat. Brakes rely on the friction between a stationary and a moving surface to generate stopping power, which means they turn the energy of the moving vehicle into heat; unfortunately heat is also the enemy of brakes. As the friction surfaces become hotter, the coefficient of friction between the two is reduced and the brakes lose effectiveness. The term that is often used to describe this is brake fade. If you’ve driven a truck down a steep grade and found it took more and more brake pedal pressure to slow down, you’ve experienced brake fade
When it comes to dissipating heat, disc brakes have a huge advantage over drums. As the caliper only covers a small part of a disc brake’s friction surface, a large portion of the rotor is exposed to air, which keeps it relatively cool. With a drum brake most of the friction surface is in contact with the brake shoes, which leaves little surface area for cooling. Consequently, compared to discs, drum brakes get hotter faster and stay hot longer. During hard or continuous use that reduces their efficiency noticeably.
Another factor that allows disc brakes to function more effectively than drums is the wiping action inherent in their design. In wet conditions the brake pads tend to wipe water off the rotor. With drums, moisture can become trapped between the shoes and drum, which lowers the coefficient of friction considerably until the water is dispersed.
For the front of his truck Jason opted for Wilwood’s six-piston calipers, which use what is called a differential bore configuration. Adapted from Wilwood’s racing brakes, it means that the piston sizes are staggered, in pairs, along the length of the caliper body. According to Wilwood, “clamping pressure is proportionately distributed to provide balanced pad loading with even wear properties at all loads and temperatures. Pad life is extended and performance is measurably improved.” In the rear, four-piston calipers were used with Wilwood’s internal parking brake, with a drum built into the rotor’s hat.
When building a custom classic truck, there are areas to cut corners, but sacrificing stopping power is not the place to do it. If you are going to drive your truck, the ability to come to a quick, straight, and safe stop is critical. And what good is a cool truck if you can’t stop it?