Caliper GP320 1.25in Bore .24in Rotor

The Wilwood Caliper GP320 1.25in Bore .24in Rotor is a four-piston aluminum brake caliper engineered for high-performance braking systems where precision stopping power and thermal stability are non-negotiable. Designed for 0.240-inch thick rotors with an 11.50-inch outside diameter, this passenger-side caliper delivers consistent pedal feel and progressive modulation across demanding duty cycles. Gray anodized construction resists corrosion while maintaining the lightweight profile essential for mobile platforms where unsprung weight directly impacts handling and fuel efficiency.

The four-piston architecture distributes clamping force evenly across the rotor, reducing pad wear variance and extending service life in comparison to two-piston designs. The 3.50-inch lug mount ensures compatibility with standard mounting bosses found on most vehicle platforms. Aluminum construction keeps overall caliper weight at 1.93 pounds—a critical factor in build-outs where suspension geometry and brake balance are tuned to specification. The 1.25-inch bore sizing pairs with the 0.240-inch rotor thickness to deliver the pressure characteristics needed for vehicles running mid-range brake pad materials and moderate to heavy duty brake applications.

Operators upgrading factory brake systems—whether for off-road recovery vehicles, towing platforms, or track-oriented builds—rely on Wilwood calipers because the specifications are repeatable and the hardware integrates into existing hydraulic circuits without requiring full system redesign. The GP320 caliper addresses the gap between budget entry-level brakes and premium race-spec units, making it the practical choice for builds where reliability and modulatable stopping force matter more than marketing. This is a passenger-side unit sold individually; match with a complementary driver-side caliper to complete a brake package.