What does a 300 N/mm spring rate mean for my car?

A 300 N/mm spring rate means that for every millimeter the spring is compressed, it exerts 300 Newtons of force. This is a relatively firm rate, suitable for performance applications where precise handling and reduced body roll are desired.

Are these springs sold individually or as a set?

These AST Linear Race Springs are sold individually. You will need to purchase the appropriate number of springs for your specific coilover setup.

What is the inner diameter of these springs?

These springs have a 61mm inner diameter. It's important to ensure this matches the perch diameter of your compatible coilover shocks for a proper fit.

Specifications

Brand: AST
Part #: AST-120-300-61
UPC: astAST-120-300-61

AST Linear Race Springs - 120mm Length x 300 N/mm Rate x 61mm ID - Single

Name: AST Linear Race Springs - 120mm Length x 300 N/mm Rate x 61mm ID - Single
Brand: AST
SKU: ast-ast-linear-race-springs-120mm-length-x-300-n-mm-rate-x-61mm-id-single-t14-329733
Price: 103.36 USD
Availability: BackOrder

$103.36

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AST Linear Race Springs: 120mm length, 300 N/mm rate, 61mm ID. Ideal for performance builds needing precise suspension tuning.

Key Features

Fits vehicles with compatible coilover systems requiring a 61mm inner diameter spring.
Features a 120mm length for specific suspension geometry requirements.
Offers a spring rate of 300 N/mm for a firm and responsive suspension.
Linear spring design provides consistent force increase during compression.
Constructed from high-tensile steel for durability and consistent performance.

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About this part

Product Details

These AST Linear Race Springs are built with a 61mm inner diameter and a 120mm length, offering a spring rate of 300 N/mm. This specific rate is chosen for applications where a firm, predictable suspension response is critical, such as track days or performance street driving. The linear rate means the spring's resistance increases consistently as it's compressed, providing predictable handling characteristics.

Constructed from high-tensile steel, these springs are made to withstand the rigors of repeated compression and extension without losing their intended rate. They are designed to work with compatible coilover systems, allowing for fine-tuning of your vehicle's ride height and corner weighting. Proper installation is key to achieving the desired suspension geometry and performance benefits.