MM Road & Track springs, 2005-14 Hardtop, Set

In stock
SKU: 435H0
Regular price $325.00
Designed for Vehicles / Universal (no vehicles listed)

MM Road & Track springs are a high-performance spring that will improve your Mustang's handling on the street, the open road, and the track. These aren't just a lowering spring, but were designed primarily to improve handling without significantly degrading ride quality. The optional short progressive-rate bumpstops allow significant lowering while maintaining good street manners. On the road and the track, these MM springs provide an excellent balance of handling and ride quality.

These springs are the heart of the MM Road & Track Grip Box for the S197 Mustang chassis. Testing showed the Road & Track Box pushed cornering power to above the 1.2g level while retaining ride quality suitable for a daily-driven Mustang.

  • Lowers your Mustang for better appearance
  • Increased spring rate reduces body roll when cornering and nose-dive when braking
  • Lowers the center of gravity for better handling
  • Quickens steering response
  • Reduces understeer
  • Spring rates chosen to maintain good level ride characteristics for reduced pitching on larger bumps


  • 1.8"-2.0" front
  • 1.9"-2.1" rear

Lowering amounts are approximate and will vary with year and model due to differences in car weight.

Spring rates

  • Front: 320-360 lb/in. The rate is progressive and approximate, ramping up from 320 lb/in at ride height to 360 lb/in at 2" of spring compression (about 1.9" of wheel travel).
  • Rear: 260-380 lb/in. The rate is progressive and approximate, ramping up from 260 lb/in at ride height to approximately 380 lb/in at 2" spring compression. Wheel travel is also 2" because the rear spring is on the axle.

For best handling balance

  • Mustangs with the same size front and rear wheels/tires will benefit from fitting a larger front swaybar, such as the Mm5FSB-10. As the next best alternative, remove the stock rear swaybar.
  • Mustangs fitted with wider rear wheels/tires than fronts will have good handling balance without any swaybar changes. To reduce body roll further, fit a complete swaybar set, such as the Eibach 35101.320.