Eibach 1200.250.0125 ERS Race Main Coilover Spring 12" x 2.5" ID x 125 lb/in

The Eibach 1200.250.0125 is a high-performance ERS (Eibach Race Spring) main coilover spring designed for racing applications and serious track enthusiasts. This precision-engineered linear-rate spring measures 12 inches in length with a 2.5-inch inside diameter and delivers a spring rate of 125 lb/in, providing the foundation for a properly tuned suspension system that maximizes traction and vehicle control.

ERS Double Spring System:

This main spring is part of Eibach's renowned ERS double-spring system, which combines main and tender springs to create a sophisticated two-stage rate characteristic. The system provides a softer initial rate when both springs compress together, then transitions to the firmer main spring rate once the tender spring fully compresses. This approach optimizes suspension compliance over road irregularities while maintaining the firmness needed to control body roll, squat, and dive during aggressive driving.

Key Features:

• Linear-rate main spring design determines the final suspension rate
• Compatible with over 700 ERS components for virtually unlimited tuning combinations
• High spring travel and deflection capability within compact mounting lengths
• Shot-peened surface treatment for enhanced fatigue resistance
• Superior dynamic durability for extended component life under racing conditions
• Manufactured to precise tolerances for consistent performance
• Advanced corrosion protection through phosphating and epoxy coating
• Clearly imprinted with part number, spring rate, and physical dimensions for easy identification
• Individually packaged for protection during storage and transport

Each Eibach ERS spring is engineered to professional racing standards, making it suitable for circle track, road racing, autocross, and high-performance street applications where precise suspension tuning is critical to performance.