Bring­ing Our Hauler to a Halt

Brakes for the 2018 United Pa­cific/ STREETRODDER Road Tour Build

Street Rodder - - Contents - By Ron Ceri­dono Photography by Brian Bren­nan and John Gil­bert

Street rod­ders tra­di­tion­ally talk about per­for­mance, which nor­mally has some­thing to do with ac­cel­er­a­tion. But in the real world de­cel­er­a­tion can be just as im­por­tant, if not more so. Think of it this way, quick 0-to-60 times are for brag­ging, quick 60-to-0 times guar­an­tee you’re around to brag about both.

To make sure our Road Tour Deuce has the stop­ping power it needs we again re­lied on Wil­wood En­gi­neer­ing. They’ve been de­sign­ing high-per­for­mance disc brake sys­tems since 1977 and can fit vir­tu­ally any need with 300 dif­fer­ent brake calipers, 200 ro­tor de­signs, 100 mas­ter cylin­der de­signs, and a wide as­sort­ment of brack­ets,

fit­tings, valves, and brake lines.

For our needs, Hot Rods By Dean (HRBD), builders of the Road Tour truck, in­stalled Wil­wood’s new Forged Dy­nalite Pro Se­ries Front Brake Kit. These kits are avail­able for tra­di­tional non-ABS spin­dle ap­pli­ca­tions on Amer­i­can mus­cle cars, vin­tage rods, and heavy weight drag cars. They’re based on the ven­er­a­ble forged bil­let Dy­nalite caliper that is suit­able for a daily driver, se­ri­ous com­pe­ti­tion, or the most dis­crim­i­nat­ing show en­thu­si­ast. Most kits re­quire no mod­i­fi­ca­tions for in­stal­la­tion, and the 11-inch rotors and com­pact calipers pro­vide plenty of clear­ance in­side most 15-inch wheels. FDL Pro-Se­ries kits can be used with ei­ther man­ual or power boost mas­ter cylin­ders.

In the rear HRBD added Wil­wood’s FDL Pro-Se­ries rear disc kits, as a clean, ef­fec­tive park­ing brake is part of the assem­bly. The kit uses forged bil­let Dy­nalite four-pis­ton calipers, 12.19inch one-piece drum/rotors with high fric­tion pads. Op­tional caliper fin­ishes and ro­tor de­signs en­able the builder to per­son­al­ize the style and op­ti­mize brake per­for­mance for ev­ery in­di­vid­ual ap­pli­ca­tion.

The heart of our brake sys­tem is a Wil­wood

alu­minum mas­ter cylin­der. They are avail­able ma­chined from high-pres­sure dies cast­ings in 7/8- or 15/16-inch bore in three fin­ishes—plain, ball bur­nished, and black e-coat. These mas­ter cylin­ders are de­signed pri­mar­ily for man­ual ap­pli­ca­tions and are de­signed for mount flanges with bolt cen­ters from 3.22 to 3.40 inches. The stroke is set at 1.10 inches with a vol­ume ra­tio of 2:1 be­tween the pri­mary and se­condary cham­bers. Ma­chined from high-pres­sure die cast­ings, each mas­ter com­mon mea­sure­ments for most do­mes­tic cars and trucks from the mid ’60s to present, and of­fer fluid out­let ports on both sides of the bore. The cylin­der weighs only 3 pounds, a 75 per­cent weight sav­ings over most cast-iron OE-type mas­ter cylin­ders. They also of­fer a com­bi­na­tion pro­por­tion­ing valve kit, which in­cludes brack­ets and stain­less lines specif­i­cally for use with this mas­ter cylin­der (PNs 260-13190 or 220-13189 for retro­fit kit).

To ad­just the front/rear brake bal­ance HRBD added one of Wil­wood’s new gen­er­a­tion of ad­justable pro­por­tion­ing valves. Pres­sure ad­just­ments range from 100-1,000 psi and pro­vide for a max­i­mum de­crease of 57 per­cent in­line pres­sure by way of a fine-thread knob. HRBD also added Wil­wood 2-pound resid­ual pres­sure valves, which re­tain min­i­mum brake line pres­sure and are ben­e­fi­cial when the mas­ter cylin­der is mounted be­low the hor­i­zon­tal plane of the calipers and fluid drain­back oc­curs from grav­ity and vi­bra­tion, re­sult­ing in ex­ces­sive caliper pis­ton re­trac­tion and a longer brake pedal stroke. The min­i­mal 2-pound resid­ual pres­sure pre­vents fluid from flow­ing back with­out caus­ing the brakes to drag (with drum brakes, a 10-pound valve is used to com­pen­sate for re­turn spring ten­sion).

Brake Pedal Guide­lines

To pre­vent the brakes from drag­ging the brake pedal must be free to re­turn com­pletely when no pres­sure is be­ing ap­plied. In some cases, the mas­ter cylin­der spring (in­ter­nal) may not be strong enough to fully re­turn the pushrod; in this case an ad­di­tional pedal re­turn spring can be used.

An­other con­sid­er­a­tion is the pedal ra­tio, or its me­chan­i­cal lever­age.

The ra­tio cal­cu­lated from the length from the pivot point of the pedal to the cen­ter of the foot pedal di­vided by the length from the pivot point to the mas­ter cylin­der pushrod. If you’re un­cer­tain about the pedal ra­tio for your ap­pli­ca­tion, a 6:1 ra­tio is an ex­cel­lent start­ing point.

Pad Bed­ding

After in­stalling and bleed­ing a new brake sys­tem it should be tested. Make a few low speed stops to check for er­ratic be­hav­ior (pulling to one side, strange noises, and so on). Check for leaks and dou­ble-check all fas­ten­ers. Once the brake sys­tem has been tested and de­ter­mined safe fol­low these steps for the bed­ding of new pad ma­te­ri­als, which ba­si­cally means driv­ing the ve­hi­cle as you nor­mally would. Ac­cord­ing to Wil­wood, “A pad is best op­ti­mized by bed­ding in the same con­di­tions and tem­per­a­tures that the pad is de­signed to op­er­ate in. A street pad can be op­ti­mized through typ­i­cal street type driv­ing. Per­form­ing a se­ries of stops that sim­u­lates street driv­ing in a safe en­vi­ron­ment will give the pads a chance to bed-in.”

We know that with the a Ford Per­for­mance Parts 347 un­der the hood the 2018 United Pa­cific/ STREET ROD­DER '32 will have plenty of go power, with the Wil­wood brake sys­tem it will have the stop­ping power to match.

■ This is Wil­wood’s Forged Dy­nalite Pro Se­ries Front Brake Kit. It came com­plete with ev­ery­thing nec­es­sary to bolt onto our early Ford spin­dles.

■ Wil­wood uses the lat­est in de­sign soft­ware and man­u­fac­tur­ing tech­niques to pro­vide state-of-the-art brakes sys­tems.

■ Wil­wood’s alu­minum front hubs are drilled for two wheel lug pat­terns, 5-on-4.5 and 5-on-4.75. There are three pieces to the front hub assem­bly—the hub, ro­tor, and adapter plate, or hat.

■ The hats are at­tached to the rotors with the sup­plied hard­ware; HRBD ap­plied thread-lock­ing com­pound to all the fas­ten­ers. Next the ro­tor/ hat assem­bly is at­tached to the hub.

Newspapers in English

Newspapers from USA

© PressReader. All rights reserved.