Wilwood 120-8062-L BNSL4R 4-Piston Radial Mount Disc Brake Caliper Left 1.25in Bore Black

The Wilwood Billet Narrow Superlite 4R (BNSL4R) is a high-performance, 4-piston radial mount disc brake caliper built for demanding competition and performance driving environments. Part of Wilwood's legendary Superlite series, the BNSL4R combines a narrow billet body design with radial mounting versatility, delivering exceptional stopping power in short track, late model, modified, open wheel, road race, off-road, rally, and sport driving applications.

Radial Mount Design: The radial mount configuration simplifies installation and provides two planes of adjustment for precise alignment over the rotor — a significant advantage over traditional axial-mount calipers in custom and competition builds.

Key Features:

• 4-piston equal bore configuration with dual 1.25 in. aluminum pistons per side for balanced clamping force and even pad wear in sustained high-heat conditions
• Narrow billet body engineered via computer-aided solid modeling and stress analysis, with closed end bridges and radial transitions to piston housings for maximum structural rigidity
• SRS stainless steel bridge plates eliminate pad gouging wear on bridge surfaces, extend caliper service life, eliminate pad rattle, and dampen harmonic vibrations that contribute to brake squeal
• Stainless steel pistons resist corrosion and retard heat transfer from the brake pads to the caliper body and fluid
• High-temperature, square-faced o-ring bore seals provide maximum sealing area, controlled piston retraction on release, and long service life in extreme heat conditions
• Internal fluid crossovers with two-piece bleed screws on each end — no external fluid tubes to snag track debris or suffer stress fractures
• Center bridge bolts replace cotter pins for added support and quick, positive brake pad retention and access
• Compatible with the full range of Wilwood PolyMatrix pad compounds to match brake response and heat range to any application
• Left-hand mount orientation with black powder coat finish
• Fits 1.10 in. rotor width; 1/8 in. NPT brake line thread

The BNSL4R is a direct-replacement caliper for all Wilwood Superlite and compatible competitive-brand calipers with 3.50 in. centered mounting tabs. Upgradeable with Wilwood's exclusive Thermlock pistons for added thermal barrier performance in the most extreme heat environments.