MM-JRi Shocks Suspension Kit, 2005-2014 Mustang



Ultra high performance suspension kit for 2005-2014 Mustangs. Suitable for competitive road racing as well as driving on the street. MM teamed with the top-level designers at JRi Shocks to create this bolt-on package for the S197 Mustang.

  • JRi Shocks monotube strut and shock design has separate adjustments for compression and rebound valving.
  • Available with your choice of front and rear spring rates.
  • Wide range of damping adjustment allows choosing softer springs for street duty, or high-rate springs for road racing.
  • Threaded-body steel coil-over strut allows easy front ride height adjustment.
  • Aluminum strut-to-spindle mounts have incremental camber adjustment to extend the range of adjustability.
  • Rear ride height adjustment is performed with an adjustable lower spring perch on the rear axle housing.
  • Includes MM caster/camber plates unique to this package.
  • Billet aluminum shocks with choice of either spherical bearing lower mount for racing, or urethane bushing for street use.
  • Helper springs maintain spring tension at full suspension droop.

When ordering, select from the options above:

  • Rear shock mounting style: Spherical bearing for track use, or urethane for least NVH in street use
  • Front spring rate
  • Rear spring rate

Contact an MM Tech Associate for help choosing spring rates.

2014 - The brand new MM-JRi dampers were driven to 2 wins in NASA American Iron races at Virginia International Raceway, both wins by Beau Dunnivant in his S197 Mustang.

2015 - Beau Dunnivant scored 2 poles and 2 more wins running on MM-JRi dampers in American Iron.

PowerGrid high performance front swaybar end links.


The collaboration of JRi and MM resulted in a suspension package that provides superior performance for the discriminating Mustang driver. The JRi design team has years of experience at the very top levels of motorsports, and the MM team applied our Mustang-specific design talent to bringing the JRi advantage to the world of Mustangs.

The result?

  • More grip
  • Better performance from improved response
  • Lower lap times
  • Easy bolt-on installation
  • Ride quality suitable for daily driving when lower spring rates are selected

The JRi Advantage
JRi has focused their engineering talents on improving the most important damper design factors.

  • Reducing breakaway seal friction (stiction)
  • Reducing internal gas spring rate and rod force
  • Reducing friction during running and side-loaded conditions
  • Reducing hysteresis
  • Increasing dynamic response at higher frequencies
  • Increasing the adjustability range
  • Stability and repeatability during temperature fluctuations

With JRi dampers on your Mustang, you will experience:

  • Improved grip on bumpy surfaces
  • Improved turn-in response
  • Reduced wheel hop
  • Consistent performance regardless of ambient temperature
  • Good ride quality with street-appropriate spring rates

Better by Design
MM focused on applying the JRi advantage to the S197 Mustang platform by bringing our wealth of Mustang knowledge, our engineering and design expertise, and our manufacturing abilities to this project.

  • We applied our usual high standards of design, manufacturing, and performance to fit the JRi struts and shocks to the Mustang.
  • Our engineers designed unique proprietary components for this project.
  • Our Lead Test Driver piloted our shop car during extensive track and street testing as we developed the valving to best suit the S197 Mustang.
  • Our high manufacturing standards perfectly suited this project.
  • American Iron multi-time Regional Champion Beau Dunnivant's favorite design feature: The ability to easily tune the handling by changing both rear springs in the pits in under three minutes.

If your needs change, these JRi dampers can be reconfigured to suit. Beyond the tuning made possible by separate rebound and compression adjustments, JRi dampers can be rebuilt with custom changes to the valves, shim stack, and bleeds. If you like testing and fine tuning everything possible, with JRi there is no need to buy new dampers; these can be serviced and customized by JRi or other competent shock rebuilder.


  • Monotube damper design, front and rear
  • Both compression and rebound adjustments are located at the top of the damper, making it very easy to make adjustments.
  • Large diameter shafts give high bending stiffness and low dynamic friction.
  • Front ride height adjusted by lower perch on threaded-body coil-over strut.
  • Steel strut body
  • Billet aluminum mounting bracket with an ingenious clamp design connects the strut housing to the spindle, while also stiffening the spindle.
  • Strut mounting ears provide additional camber adjustment in finite increments.
  • Strut ears can be mounted to strut housing at different heights, allowing adjustment of bump/droop travel without making any internal changes to the strut.
  • Front spring couplers (between the helper spring and the standard spring) have a Teflon guide to prevent wear of the strut body threads.
  • New strut-to-spindle hardware (Ford lists this hardware as one-time use)
  • Bolt-on swaybar end-link mounting brackets securely clamp to the strut housing.
  • Lightweight aluminum shock body
  • Rear ride height can be changed by aluminum adjuster mechanism on top of the axle.
  • Lower rear shock mount available in choice of spherical bearing or high-grade urethane.
  • Your choice of spring rates
  • Top-quality 2.5" springs, front and rear
  • Low-rate helper springs ensure tension on the main springs at full droop, preventing the springs from coming off the spring perches.
  • Thrust bearings on front upper spring perch prevent any effect on steering effort.
  • MM Caster Camber Plates



  • 2011-2014 spindle
  • 2005-2014 chassis

Does NOT fit

  • 2005-2010 spindle. This spindle has a narrower strut mounting ear than the 2011-2014 spindle. The 2005-2010 spindle also only fits the undesirable smaller diameter 2005-2010 ball joint. Swapping your front control arms and spindles for the much-improved 2011-2014 versions is an upgrade you won't regret!

Shipping Information

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