C/O Spring - 2.5in ID x 10in Chrome

The C/O Spring – 2.5in ID x 10in Chrome by QA1 is a coil-over spring engineered for high-performance suspension tuning and custom vehicle builds. Whether you're upgrading a street rod, race car, or daily-driven performance vehicle, this chrome-finished spring provides the foundation for precise ride height and load support. Built by QA1, a trusted name in suspension dynamics, this component is ideal for enthusiasts seeking repeatable handling characteristics and professional-grade damping control when paired with a complete coil-over assembly.

The 2.5-inch inner diameter and 10-inch free length make this spring compatible with most modern coil-over setups, offering a balance between ride quality and chassis stiffness. Chrome plating protects against corrosion while delivering a polished appearance—critical for show vehicles or builds where aesthetics matter as much as function. The spring rate and preload characteristics work in concert with adjustable coil-over bodies to dial in corner weights, anti-squat geometry, and roll stiffness with surgical precision. At 3.44 pounds, it's lightweight enough for serious weight-conscious builds without sacrificing structural integrity or fatigue resistance under repeated compression cycles.

This spring performs best in applications where coil-over suspension geometry is already established—race cars, drag vehicles, road-course machines, and restomod platforms benefit most from QA1's precision spring design. Installation requires pairing with a compatible coil-over body and shock absorber; verify your vehicle's suspension dimensions and spring rate requirements before ordering. The chrome finish resists road salt and weather exposure, making it suitable for both garage queens and tracked vehicles. For serious suspension work, consult chassis dynamometer data or a suspension tuner to select the optimal spring rate for your specific weight distribution and intended use case.