Aftermarket Product Guide

DYNAPRO Big Brake Front Kit

Cavalier/Sunfire Wilwood Front Brake Install
03-30-2005

When modifying a J-Body, one of the first things to realize is that the suspension needs some close attention. For a true-performance vehicle, a tuner must understand that single-piston front brakes with an 8-inch rotor are not going to cut it on the track. This being the case, the experts at Wilwood Engineering in Camarillo, CA developed a front brake upgrade for 95-04 J-Bodies that brings race-proven technology to your vehicle.

First debuted on the Motegi Racing Wheels 2003 Chevrolet Cavalier SEMA car, which was featured in the August issue of HCI Magazine, The Wilwood brake conversion proved to be one of the most valuable additions to the vehicle. This particular Cavalier was boasting over 250+ hp at the wheels and over 245 ft. lbs of torque from turbo and nitrous upgrades, and thus needed to be able to stop with some authority. Wilwood provided that for the project.

The 12-inch, 4-piston caliper front brake upgrade is in production and Wilwood estimates that the 12-inch disc rear-brake conversion for the J-Body should be available by summer 2005.

For installation, it is recommended that the kit be assembled and installed by a professional mechanic with experience in brakes. The following step by step install article provides images and details, which topped out at roughly 3 hours.

Step 1: The rotors and hats must be assembled. The 8 hex bolts are bolted into the back of the rotor securing the hat. Once all bolts are tightened down, safety wire is then threaded, wound and cut to ensure the bolts will not fall in the unlikely case of them backing out. Safety-wire pliars are recommended for this step. A set can be purchased from any auto store for around $60.


Step 2: With the rotors assembled, the next step is jacking up the car. The install can be done on either a lift, or simply raising the front of the vehicle onto jack stands. Then remove the wheels.

Step 3: Using a socket and rachet, remove the stock caliper. NOTE: Do not unhook the brake line. Leave the stock caliper connected and simply let it hang away from the work area. This will prevent loss of brake fluid.

Step 4: Remove stock rotor.

Step 5: This is the most difficult step of the install. The stock spindle must be modified to make room for the larger rotors. The upper and lower caliper slides must be ground down roughly 1.7 inches. A hand grinder is the best tool for this step. First, mark the spindle clips with a grease pen as a guide. Cut clips.

Step 6: With the caliper slides removed, the area must be smoothed down to ensure no burrs or sharp edges exist. Once smoothed, place the new rotor assembly onto spindle to check for clearance. If the rotor is touching, remove and shave spindle further to ensure proper clearance.

Step 7: Next, install the caliper-mounting bracket to the spindle. This bracket utilizes the same holes the stock caliper mounts to. Add or remove shims to the mounting bolts to achieve proper clearance for the caliper. Bolt on new rotor with 2 lug-nuts for balance.

Step 8: Next is the assembly of the caliper with the pads. Remove caliper quick-clip retainer from the caliper. Remove the protective material from the adhesive side of anti-squeal shims. Place against back of brake pads. Gently bend shim tabs over pad with a hammer. Reinstall caliper quick-clip.

Step 9: Install caliper onto caliper mount. Check for clearance of rotor within caliper. If spacing must be changed, add and remove black shims to caliper mounting bracket until ideal spacing is achieved. Secure caliper to mounting bracket with socket and rachet.

Step 10: Remove sticker from back of caliper and install brake line feed. The GME installation utilized the optional Wilwood braided stainless steel hose kit (Part#: 220-8422). Tighten the line so that the feed is facing down. Install brake line to feeder.

Step 11: Unhook stock brake line and install Wilwood stainless line.

Step 12: Check all mounting points to ensure they are torqued to the proper weight and that clearance of rotor is still safe at both the spindle and caliper.

Step 13: Bleed the brakes to ensure ample amount of fluid is running to the caliper.

Step 14: Remove lugs from rotor, install wheel, tighten lugs.

Step 15: Repeat procedure on other side of vehicle.