QA1 2-1/2in ID High Travel Spring - 9in Length x 180lbs/in - Silver Powder Coated

High-Travel Coilover Spring Built for Performance Suspension Tuning

The QA1 9HT180 is a 9-inch free length, 180 lb/in linear rate coilover spring with a 2.5-inch inside diameter, purpose-built for high-travel suspension systems. Constructed from high-tensile chrome-silicon alloy wire, it requires fewer coils than conventional springs, reducing unsprung weight by up to 28 percent and increasing usable suspension travel by up to 20 percent. The square-end configuration seats flush against standard coilover perches, and the silver powder coat finish provides lasting protection against corrosion. This is a universal-fit spring designed to work with any coilover shock that accepts 2.5-inch ID springs with at least 9 inches of available spring seat space, from road race builds and autocross setups to drag suspension and street performance applications.

Features

• High-travel design provides up to 20 percent more usable suspension travel compared to conventional springs of the same rate
• Chrome-silicon alloy wire construction reduces weight by up to 28 percent versus standard springs
• Linear 180 lb/in spring rate delivers predictable, consistent response throughout the entire stroke
• 2.5-inch inside diameter fits standard coilover hardware
• 9-inch free length
• Square ends top and bottom for flush perch seating
• Silver powder coat finish for corrosion resistance and a clean appearance
• Made in the USA
• Sold individually

Universal Application and Fitment

This is a universal coilover spring. It does not correspond to a specific vehicle year, make, or model. It fits any coilover shock absorber that uses a 2.5-inch inside diameter spring and provides at least 9 inches of available spring perch travel. To confirm fitment, measure the inside diameter of your existing coilover spring or the coilover body at the spring seat. Then verify that the shock has at least 9 inches of clearance between the upper and lower spring perches at full droop. If your current spring is shorter or has a different inside diameter, cross-reference with QA1 spring dimensions before ordering. Common applications include circle track, road race, autocross, drag racing, and performance street builds using coilover suspensions.

Specifications

What Is Included

• 1x QA1 9HT180 high-travel coilover spring

Frequently Asked Questions

What coilovers does this spring fit?
This is a universal spring. It fits any coilover shock that accepts a 2.5-inch inside diameter spring and has at least 9 inches of available travel between the spring perches. It is not vehicle-specific. Verify your coilover spring ID and available perch spacing before ordering.

What is the spring rate in kg/mm?
This spring has a linear rate of 180 lb/in, which is approximately 3.22 kg/mm. That figure is calculated by dividing 180 by 55.997, the conversion factor from lb/in to kg/mm.

Is this spring sold as a single unit or as a pair?
It is sold individually, as one spring per order. If you need a matching pair for a two-corner or four-corner application, order two units.

How do I verify this spring will work with my coilover shock?
Measure the inside diameter of your current coilover spring or the diameter of the coilover body at the spring seat. It should measure 2.5 inches. Then measure the available distance between your upper and lower spring perches with the shock at full droop. That measurement should be at least 9 inches. If both dimensions match, this spring is compatible with your coilover.

What does this spring weigh?
This spring weighs approximately 2.37 lbs. The high-travel design uses fewer coils and a smaller wire diameter than conventional springs of the same rate, resulting in meaningful unsprung weight reduction.

Can I mix different spring rates front and rear?
Yes. Mixing spring rates front to rear is a common tuning technique used in road racing, autocross, and drag racing to adjust understeer and oversteer balance. Running 180 lb/in on one end while using a different rate at the other is acceptable as long as both springs share the same 2.5-inch inside diameter. Always consult your chassis setup specifications and perform on-track testing to dial in the balance for your application.

Will installing this spring void my vehicle warranty?
Under the Magnuson-Moss Warranty Act, a manufacturer cannot void your vehicle warranty simply because you installed an aftermarket part, unless they can demonstrate the aftermarket part directly caused the failure in question. Installing coilover springs alone does not automatically void your powertrain or manufacturer warranty. Review your vehicle warranty terms and consult with your dealership if you have specific concerns before making suspension modifications.

What is the difference between a QA1 high-travel spring and a standard linear spring?
Standard linear coilover springs use a conventional coil pitch and wire diameter. QA1 high-travel springs use fewer coils with a wider coil spacing, which allows the spring to compress further before coil bind. The result is up to 20 percent more usable suspension travel compared to a conventional spring of the same rate and length. The reduced coil count also lowers spring weight by up to 28 percent. The spring rate behavior remains linear throughout the stroke.

Installation Instructions for Coilover Spring Replacement

1. Park the vehicle on a level surface and engage the parking brake. Place wheel chocks behind the rear wheels if working on the front suspension.
2. Loosen the wheel lug nuts slightly before raising the vehicle. Use a floor jack rated for your vehicle's weight and position it at the manufacturer-specified lift points.
3. Raise the vehicle and support it on quality jack stands placed at frame or subframe contact points. Never work under a vehicle supported only by a floor jack.
4. Remove the wheel and tire to access the coilover assembly.
5. If equipped with external brake lines, ABS sensor wires, or other components routed near the coilover, carefully detach or reposition them to avoid stress during spring removal.
6. Using a coil spring compressor appropriate for the coilover style, compress the spring enough to relieve tension from the perch. Do not remove more tension than necessary. Improper spring compression is a safety hazard.
7. Loosen and remove the top mount fasteners or coilover upper mounting hardware per your coilover manufacturer's instructions. Support the lower control arm or shock body so it does not drop suddenly.
8. Slide the old spring off the coilover body. Note the orientation of any spring perch adjustment collars, bump stops, or helper springs before removal so you can replicate the setup during reassembly.
9. Inspect the coilover shock body, perches, and threads for wear, damage, or corrosion. Address any issues before installing the new spring.
10. Slide the new spring onto the coilover body, ensuring the square end seats flat and flush against the lower perch.
11. Reinstall the top mount and upper perch hardware. Torque all fasteners to the coilover manufacturer's specified values.
12. Slowly and evenly release the spring compressor, confirming the spring seats properly on both the upper and lower perches without shifting.
13. Reinstall any brake lines, ABS wires, or other hardware that were removed or repositioned in step 5.
14. Reinstall the wheel and tire. Lower the vehicle and torque the lug nuts to the vehicle manufacturer's specification in a star pattern.
15. After installation, perform a four-wheel alignment to correct any camber, caster, or toe changes introduced by the new spring rate or ride height adjustment.

WARNING: This product can expose you to chemicals including lead and phthalates, which are known to the State of California to cause cancer and reproductive harm. For more information go to www.P65Warnings.ca.gov.