SCORE Journal - The Official Publication of SCORE Off-Road Racing
Issue link: http://read.uberflip.com/i/519117
CALIPERS-THE HEART OF A RACING BRAKE SYSTEM Most people don't realize all the design efforts and technology that go into a racing brake system, but there's much more happening with these components than what can be seen from the outside. Racing calipers, for example, have lots of engineering behind them that over many years, have been adapted to the specific circumstances desert racing vehicles face in competition. For starters, a majority of racing calipers in the Unlimited classes are a mono-block (one piece) design. Mono-block calipers prevent deflection which can minimize its overall clamping force. "The biggest advantage of the mono-block design is that they are extremely rigid," explains Rick Elam from BAER Brakes. "The more rigid you can make a caliper the better, as you are not sacrificing performance due to deflection." Deflection can come from the pressures that the caliper can apply to the brake pads and rotor, and the force that pushes back against the caliper under hard braking. So many racing mono-block calipers are machined from billet aluminum alloy and feature four to six pistons that provide even brake pad pressure that optimizes the use of the full pad-face against the rotor. "The goal is to spread the pistons along the backing plate of the pad to control the pad, and minimize pad taper," says Elam. "With most current pad sizes and shapes we have found that six pistons are the optimum number for overall pad control. More pistons could be added, but at some point it is more of a marketing advantage rather than performance." Longevity during a 500 or 1000 mile race is also key to a racing brake system. According to the engineers at Brembo, off-road racing applications require very stable performance in all the different conditions that can include sand, mud, standing water, cold and hot. The company's engineers also say that the overall wear needs to be taken into consideration as well, and in the case of their products, the components in the caliper are sealed and enclosed to protect them from rocks, sand, silt and mud. In addition, off- road racing courses also have a multitude of obstacles and road hazards such as rocks, branches, and flying parts. So over the years, brake manufacturers have made adaptations to their caliper design that reduce the chance for damage during a race, and to promote increased cooling. "Our mono-block desert racing caliper design features internal fluid channels to remove the need for an external fluid transfer pipe that could be subject to damage in a desert race," says Alex Hargreaves, Alcon Motorsports Manager. "These calipers also feature recessed and capped bleed screws and underside positioning of the fluid inlet port to further minimize the chance of damage." BREMBO'S RACING CALIPER FOR BUGGIES IS A MONOBLOCK DESIGN THAT ELIMINATES DEFLECTION AND CAN BE USED IN A VARIETY OF CLASSES OF LIGHT-WEIGHT VEHICLES. 061 SCORE JOURNAL