SKU: AST-180-100-61 | UPC: astAST-180-100-61
AST Linear Race Springs - 180mm Length x 100 N/mm Rate x 61mm ID - Single for 2006-2015 Mazda MX-5 Miata, BMW 3 Series E90/E92
AST Linear Race Springs deliver consistent 100 N/mm rate across 180mm free length with 61mm inner diameter for coilover systems. Fits 2006-2015 Mazda MX-5 Miata and BMW 3 Series E90/E92 models in track setups. Linear design ensures predictable response improved cornering stability and reduced body roll during aggressive driving.
Key Features
- 100 N/mm Linear Rate: Maintains steady force for balanced weight transfer and neutral handling in high-speed turns
- 180mm Free Length: Matches common coilover perch spacing for proper sag and ride height adjustment
- 61mm Inner Diameter: Slides perfectly over 2.5-inch coilover struts used in Miata and BMW applications
- Chrome Silicon Steel: High-tensile wire withstands repeated track abuse with shot peening for fatigue resistance
- Heat Treated Construction: Stress relieved and preset to hold shape under extreme loads and temperatures
Product Notes
- Sold as single spring order pairs for front or rear axle replacement
- Special order item with current clearance pricing available
- Store in dry conditions to prevent corrosion on powder coated finish
Installation Notes
- Professional installation recommended.
- Match spring rate to paired damper valving for optimal damping
- Compatible with AST 503/5300 series coilovers and similar 61mm ID bodies
This Part Fits
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2006-2015 | Mazda | MX-5 Miata | Base, Grand Touring, Sport |
| 2006-2013 | BMW | 3 Series | E90 Sedan, E92 Coupe, E93 Cabrio |
| 2005-2012 | Porsche | Boxster | Base, S (987) |
| 2007-2013 | Subaru | Impreza WRX STI | All |
Why Choose AST?
- Proven in European GT racing and NASA series events
- Hand-built in Netherlands with laser-measured tolerances
- Direct replacement for factory coilover springs in multiple chassis
Frequently Asked Questions
-
Q: Will this spring fit my Mazda MX-5 Miata coilover kit?
A: Yes fits AST 5300 and similar systems on 2006-2015 NC Miata with 61mm ID strut bodies verify perch setup before install -
Q: What material and finish does it have?
A: Chromium-silicon high-tensile steel shot peened heat treated and black powder coated for rust protection and durability -
Q: What warranty coverage applies?
A: 1-year manufacturer warranty against defects when installed by certified shop includes material and workmanship
Shipping & Handling
- Method: UPS Ground or FedEx Ground
- Availability: In stock - ships same or next business day
- Packaging: Protective fiber tube 8 x 3 x 3 inches
- Weight: 2.2 lbs
AST
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