What is the main benefit of Thermlock® pistons?

Thermlock® pistons are designed to block heat transfer from the brake pads. This can significantly reduce temperatures within the caliper, brake fluid, and seals, by up to 25% compared to standard stainless steel pistons.

How do differential bore pistons help with brake pad wear?

Differential bore pistons compensate for differences in mechanical loading and temperature across the brake pad surface. This helps to reduce taper wear, leading to more even pad usage, especially in high-temperature situations.

What kind of applications are these calipers best suited for?

These calipers are well-suited for sustained hard braking in demanding applications such as dirt and asphalt ovals, off-road driving, rally racing, and road course use where heat management is critical.

Wilwood ST FSL4R Brake Caliper 1.88/1.75 1.25 Rotor 120-1326

Name: Wilwood ST FSL4R Caliper 1.88/1.75 1.25 Rotor
Brand: Wilwood
SKU: wilwood-wilwood-st-fsl4r-caliper-1-88-1-75-1-25-rotor-t14-582094
Price: 468.61 USD
Availability: InStock

Wilwood ST FSL4R Caliper 1.88/1.75 1.25 Rotor

$468.61

Only 1 left in stock

Wilwood ST FSL4R Caliper 1.88/1.75 1.25 Rotor. Features Thermlock® pistons to reduce caliper temps by up to 25% for sustained hard braking.

Key Features

This product is a Wilwood ST FSL4R brake caliper.
Features differential bore pistons (1.88-inch and 1.75-inch) to reduce pad taper wear.
Includes Thermlock® pistons that block heat transfer, reducing caliper temperatures by up to 25%.
Designed for use with a 1.25-inch rotor.
Has a wear-resistant Type III hard anodize finish for durability.
Suitable for sustained hard braking in off-road, rally, road course, and oval track applications.

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Product Details

This Wilwood ST FSL4R caliper kit includes one caliper with differential bore pistons (1.88-inch and 1.75-inch) and Thermlock® pistons, designed for use with a 1.25-inch rotor. These calipers are built to handle the demands of sustained hard braking, making them a solid choice for various racing and performance driving applications like dirt and asphalt ovals, off-road, rally, and road courses.

The key advantage here is the combination of differential bore pistons and Thermlock® pistons. The differential bores help manage pad wear by accounting for leading-edge loading and temperature differences across the pad surface, reducing taper wear. The Thermlock® pistons are a notable feature; they actively block heat transfer from the brake pads, which can lower caliper, fluid, and seal temperatures by as much as 25% compared to standard stainless steel pistons. This improved heat management is crucial for maintaining consistent braking performance under extreme conditions.

Finished with a wear-resistant Type III hard anodize, these calipers are built for durability in harsh environments. They are a well-built option for anyone looking to upgrade their braking system for more demanding use.