AST Linear Race Springs – 150mm Length x 90 N/mm Rate x 61mm ID – Single

This AST Suspension Linear Race Springs – 150mm Length x 90 N/mm Rate x 61mm ID – Single is a single linear race spring selected by free length, inner diameter, and spring rate. Match all three dimensions to the suspension system and corner-weight target rather than selecting it by vehicle name alone.

Key Features

• 150mm Free Length: Matches high travel coilover designs allowing full suspension droop and bump without binding.
• 61mm Inner Diameter: Compatible with common 2.4-inch coilover perches for direct bolt-on integration.
• Chrome Silicon Steel Construction: Heat treated and shot peened for fatigue resistance enduring thousands of race cycles.
• 90 N/mm Linear Rate: Provides steady force progression for sharp responsive handling and control through corners.
• Powder Coated Finish: Resists corrosion from track elements and repeated washdowns maintaining performance.
• Compatible with AST coilovers and 61mm ID perches requires no special hardware.

Fitment

This component is selected by its exact dimensions, rate, interface, capacity, or service application rather than passenger-vehicle year, make, and model.

Specifications

What’s Included

One new AST Suspension product in the exact part number, dimensions, rate, adjustment specification, and quantity identified on this page. Springs, dampers, top mounts, reservoirs, adjusters, links, tools, lines, fittings, and hardware are included only when expressly stated for this exact configuration.

About AST Suspension

AST Suspension develops performance springs, dampers, coilovers, top mounts, and motorsport suspension components. Vehicle fitment, dimensions, rates, adjustment functions, and included components remain exact-part specific.

Related Parts

• Shop the complete AST Suspension collection
• Shop suspension components
• AST Linear Race Springs – 140mm Length x 100 N/mm Rate x 61mm ID – Single
• AST Linear Race Springs – 140mm Length x 80 N/mm Rate x 61mm ID – Single
• AST Linear Race Springs – 140mm Length x 90 N/mm Rate x 61mm ID – Single

Frequently Asked Questions

How do I choose the correct AST race spring?
Match free length, inner diameter, spring rate, available suspension travel, corner weight, motion ratio, preload target, and the damper manufacturer’s spring specification.

Is this spring vehicle specific?
No. A linear race spring is selected by dimensions and rate for a compatible coilover or damper assembly, not by year, make, and model.

Is the listed rate for one spring?
The rate applies to the exact single spring shown on this page. Confirm the included quantity before ordering a complete axle or vehicle set.

Can I substitute a spring with a different free length?
Only after verifying perch adjustment, installed height, preload, bump and droop travel, coil bind, and clearance for the complete suspension system.

Installation Instructions

1. Confirm the exact AST part number, complete application or dimensional specification, included components, and current instructions before disassembly.
2. Support the vehicle at approved points and record the original ride height, alignment, suspension orientation, and adjustment settings.
3. Install components in the specified position and sequence using correct spring-compression, torque, preload, ride-height, and damper setup procedures.
4. Verify full suspension and steering travel, tire and wheel clearance, brake-line routing, fastener torque, and damper operation.
5. Settle the suspension, measure final ride height, complete a professional alignment, and recheck the installation after the initial driving cycles.