Wilwood’s GN lll is a time proven caliper that has been widely used with 5 on 5 hubs for stock car, road course, and off-road competition. The 3.50" mount configuration (also available in 6.00” mount) incorporates this legacy of enduring performance, with options available for the latest brake system heat management technology.
3.50" mount with taller height for 12.19" rotors. The new generation GN lll uses the same popular 3.50" mounting pattern found on the Superlite caliper series, but are built with a taller mounting height. This feature accommodates the installation of 12.19" diameter rotors on the same spindle brackets used with a Superlite caliper and 11.75" diameter rotor. The GN lll can be run with either a 1.25" or 1.38" thick rotor. This makes it possible to run three different bolt-on brake setups, without the need for bracket changes on the spindle.
High strength, low deflection, and superior stopping power. Each GN lll is manufactured from a precision casting using a tight grained, high-density aircraft alloy. It is a two-piece, closed bridge design with grade 8 thru-bolts and external stiffening ribs. The GN lll utilizes a unique six-piston configuration that generates high clamping force with balanced loading for extremely even pad wear. The 1.75" / 1.38" / 1.38" bore pattern contains a total of 5.44 square inches of effective piston clamp area. This makes the GN lll one of the largest calipers available, with weights starting at 5.94 pounds. The caliper bridges are fitted with stainless steel plates to reduce wear and provide smooth pad operation. Dual center bridge bolts add to the overall caliper strength and provide positive retention for the top loaded pads. Dollar for dollar, this combination is unmatched for high strength, low deflection, and superior stopping power.
Additional Notes
Thermlock® or stainless steel pistons. The standard GN lll uses six stainless steel cup pistons. Stainless is used for its slow heat transfer properties and high corrosion resistance. The GN lll/ST models feature Wilwood’s exclusive Thermlock® pistons to minimize the direct heat transfer from the pads. These pistons can reduce caliper temperatures by more than 30% over stainless steel pistons, without the need for fluid recirculation systems. Fluid temperatures are reduced, seal life is extended, and caliper service life is prolonged with less distortion and reduced wear in the piston bores. Cooler temperatures translate into maximum performance and ultimate reliability over the longest run. Thermlock® pistons are also available for the 6.00” mount, see page 109 for details. Using EXP 600 Plus racing brake fluid will guarantee success with trouble free performance in all extreme conditions. The 3.50" mount GN Ill calipers use the 7520 style pad. The longer and wider pad face provides a full two cubic increase in pad volume over a 7320 style Superlite pad. Larger pads mean longer wear and additional heat resistance in extreme duty conditions. Four brake compounds are available to match brake torque and heat range requirements on any application.
About Wilwood Engineering
Wilwood Engineering designs and manufactures high-performance disc brake systems. Since the company’s inception in 1977 by Bill Wood, we have developed a substantial matrix of brake components and engineering techniques that allow us to quickly and reliably create brake systems for almost any application. Our core ability is the rapid development of custom engineered brake systems using a combination of off-the-shelf and custom components. In addition to designing and manufacturing brakes for all types of competitive motor sports, Wilwood also manufactures brake systems and components for agricultural equipment, industrial applications, utility vehicles, snowmobiles, quads, motorcycles and military vehicles.
With headquarters in Camarillo, California, Wilwood employs approximately 250 people. We have on-shelf stock of more than 300 different brake calipers, 200 rotor designs, 100 master cylinder designs and a wide assortment of brackets, fittings, valves and brake lines. Our off-shelf brake calipers range in size from tiny calipers used on go-carts and light duty industrial equipment, to heavy duty original equipment brakes for the U.S. military Humvee.
Wilwood's engineering department uses the latest computer-aided design and manufacturing techniques in conjunction with finite element analysis, dynamic test and cycle test equipment, to find high-performance and reliability solutions for the most difficult braking tasks. Our extensive inventory of proprietary on-the-shelf components allow us to provide cost-effective solutions for unique brake applications.
Wilwood is ISO 9000 compliant and has extensive experience maintaining quality levels of 100ppm or less for original equipment manufacturers.
