Wilwood High Volume Aluminum Master Cylinder

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Wilwood High-Volume aluminum master cylinders represent the latest refinements in brake pressure actuation and fluid control. Each master-cylinder is high-pressure die-cast from high-grade aluminum, fully machined and assembled with exclusive features only available from Wilwood. These master cylinders have the highest fluid capacity of any integral reservoir design. With a total capacity of 8.2 ounces, there is at least 26% more fluid than most competitive brands. More fluid volume means cooler temperatures and additional insurance for extreme conditions where high pad wear can compromise fluid levels during long events. With 1-7/16'' of piston travel, there is plenty of margin when used with large four and six piston calipers. Most other brands of aluminum master cylinders are sand castings.

Sand castings have rougher and less accurate finishes than die-castings and are more prone to porosity and pitting when the bores are machined. Consequently, sand-cast cylinders must be fitted with a stainless sleeve to achieve a smooth bore finish. The sleeve not only inflates the price of the master cylinder, but it also retains heat longer causing higher operating temperatures inside the piston bore. The accuracy of high-pressure die-casting allows Wilwood aluminum master cylinders to leave the mold at near finished bore size. First, the fluid feed and pressure compensation holes are drilled from the reservoir chamber to the piston bore. Then, a special micro-finishing process produces a porosity free bore that provides superior seal life, long wear and better heat dissipation than stainless steel sleeved models. Bore diameter and taper tolerances are held tight to assure proper seal contact and the elimination of any potential pressure loss from bypassing under load.

An internal slosh baffle guarantees a constant fluid supply to the bore chamber during hard cornering, acceleration and braking. This unique baffle also eliminates aeration into the reservoir from return fluid that can occur during braking release and bleeding procedures. Heavy-duty internal piston springs provide fast retraction for immediate release and positive fluid transfer without the need for cumbersome external pushrod springs. Pedal feel is improved, piston retaction is guaranteed, fluid recovery is quicker and the bleeding process is simplified. Formed steel lids, heavyweight bail wires and bellows type gaskets keep the fluid in and the moisture out with correct pressure balancing during fluid displacement. Wilwood master cylinders use common dimensions for either flange or side mounting with 1/8''-27 NPT fluid ports for easy interchange with all other racing master cylinders.