The Wilwood 120-11576 is a four-piston caliper from the Forged Narrow Mount Dynalite (FNDL) line, sized for a 1.25 rotor width and 3.50 mount center with a lug-style mount. Its forged aluminum body is stress-flow forged, a process the manufacturer says avoids the grain interruptions left by machining a straight block billet. Stainless 1.38 pistons and Wilwood's stainless SRS bridge plates complete the build.
Compared with a stock or budget caliper, the value here is strength and simplicity under race loads. The manufacturer positions the FNDL design for late models, modifieds, sprints, off road and road racing, and claims it is stronger than comparable calipers in its class. Internal fluid passages remove the external crossover tubes that can snag or leak, and the stainless pistons help limit heat moving into the pads. Pad choice can be tuned through the full range of PolyMatrix pad compounds. Search terms this suits include "FNDL 3.50 lug mount caliper," "1.38 piston 1.25 rotor race caliper," and "Wilwood 120-11576 sprint car brake."
Per the manufacturer, FNDL calipers are a direct replacement for all previous Wilwood NDL calipers and similar competitive brands with 3.50" centered mounting tabs.
The manufacturer states that four corner bleed screws allow one caliper to be mounted in any front, rear, right, or left position.
Confirm your hub or spindle provides a 3.50-inch centered lug mount before ordering, since that is the fitment dimension this caliper is built around. The manufacturer's guidance for Wilwood calipers says to fill and bleed the system with Hi-Temp 570 grade fluid or higher, and for severe or sustained high-heat use, EXP 600 Plus racing fluid. Bleed starting with the caliper farthest from the master cylinder, and bleed only from the top screws. Wilwood's bleeding notes say the lower screws are there only for mounting on either side and should not be bled. The manufacturer also notes that OEM rubber brake hoses generally cannot be adapted to Wilwood calipers, so plan on steel adapter fittings and braided line. Check for leaks after bleeding and confirm a firm pedal before driving.
