FAQs & Tech Tips

MM News

MRT Exhaust! MM now offers premium MRT cat-back exhaust systems for 1996-2004 Mustangs.

New! for Street & Strip Mustangs! Big-bore rear wheel cylinders for 1979-1993 Mustang with 9" drum brakes. Improves braking when running big rear tires and front skinnies, and/or different OEM front brakes.

New! Swapping a Coyote into a Fox Mustang? MM's Hydroboost Conversion Kits allow easy installation of a 1996-2004 Mustang Hydroboost power brake assist unit into a 1979-1993 Mustang.

New! Swapping an IRS into your Fox Mustang? MM makes it easier with a brake line kit made just for this conversion. Bolts-in, with no cutting or flaring of brake lines. Designed to fit standard IRS brake hoses.

New! MM's billet aluminum Pedal Box Spacer for Fox Mustangs. Replace the breakage-prone OEM plastic spacer when converting to manual brakes or Hydroboost.

Canadians! Please read the latest about ordering from Canada/shipping to Canada.

/DRIVE
We've posted the parts list and link to the video of MM's Mustang in /DRIVE Tuner car Shootout

Coil-Over Kit with Springs, Koni Shocks, rear, 1979-04 Mustang non IRS
Actual product may differ from photo.

$476.94

  • Item # COP-5
  • Manufacturer: Maximum Motorsports

Select Option(s):

Rear Spring Rate Choice










 
Add second rear lower shock mount?

 

 

Larger Image

MM Rear Coil-over Conversion package with springs fits solid axle-equipped 1979-2004 Mustangs. Does NOT fit IRS shocks.

Fits
  • Koni Single Adjustable shock 8041-1186S. Listed by Koni for 1994-2004 solid axle-equipped Mustangs, it's also the MM-recommended rear shock for Fox Mustangs because it has an easily removable dust boot for coil-over conversion.
  • Koni Double Adjustable shock 8042-1134S. Listed by Koni for 1994-2004 solid axle-equipped Mustangs, it's also the MM-recommended rear shock for Fox Mustangs because it has an easily removable dust boot for coil-over conversion.
Does NOT fit
  • Any Koni rear shock listed for 1979-1993 Fox Mustangs. The several variations of Koni shocks built for those model years include features that make them unusable for a coil-over conversion. These features include a welded-on steel dust cover, different diameters that do not fit the MM threaded sleeve, and the requirement to remove the shock from the vehicle to adjust it.
  • Koni STR.T shocks. These have a welded-on steel dust cover and valving too soft to control a coil-over spring.
  • Any Koni shock listed for the 1999-2004 Cobra IRS.

Aggressive front coil-over spring rates mandate converting your Mustang's rear suspension to a modern coil-over design to achieve the best handling balance. When higher wheel rates are desired, rear coil-overs provide better handling and ride quality than do high-rate stock location springs for your 1979-2004 Mustang.

MM's conversion kit for Fox and SN95 Mustangs allows easy ride height adjustment without changing springs. Our kit:

  • Improves handling and ride quality by swapping the stock-location rear springs for springs located on the shocks.
  • Lets you choose what spring rate is best for how you use your Mustang. A wide variety of spring rates are available.

Requires shock-to-axle mounting brackets
Coil-over installation requires a robust lower shock-to-axle mounting bracket.

  • If you have an MM Panhard Bar, the axle mount does double duty as the lower shock mount for the driver side. Only 1 shock-to-axle mounting bracket (MMSM-2) is required for the passenger side, and is included in the MMCO-5 kit.
  • If you don't have an MM Panhard Bar, you'll need 2 of the shock-to-axle mounting brackets (MMSM-2). Order a second bracket by selecting the "Yes, add the MMSM-2" option button above.
Notes
Coil-over benefits
  • Ability to choose from a wide range of spring rates, from firm to very stiff.
  • Improves handling (reduces body roll and quickens steering response) without degrading ride quality because the coil-over spring location improves the motion ratio. This allows a much higher wheel rate than is possible with a stock-location spring.
  • Improves ride quality by eliminating a source of friction in the rear suspension, letting the suspension move more freely and thus reducing harshness.
  • Provides easy ride height adjustment.
  • Reduces unsprung weight, which improves handling and ride quality.
  • Allows for easy spring swapping.
  • Ride height can be retained after swapping to springs with a different rate.
  • Allows adjusting corner weights for optimal track performance.
  • Upper shock mounts reduce deflection, improving damper control.

For help choosing springs, see the MM Guide to Choosing Spring Rates and Dampers.

Features
  • Package includes pair of springs at a discounted price.
  • Only fits Koni Single Adjustable and Double Adjustable shocks listed for SN95 Mustangs with a solid rear axle. Those shocks easily retrofit to a Fox Mustang.
  • This is not an ill-fitting universal kit. It's designed to have a snug fit over the shock housing to prevent rattling.
  • No physical modifications to the shock needed for installation.
  • Threads are hard-anodized for longevity and easier adjustment of the spring perch.
  • Lower spring perch has Nylon-tipped stainless steel set screws to prevent unwanted rotation.
  • Includes robust urethane lower shock eyelet bushings.
  • Includes one MMSM-2 Lower Shock Mount. If your Mustang does NOT have an MM Panhard Bar, click on the "Yes, add the MMSM-2" option button above to add a second lower shock mount to this order.
Fits
  • Koni Single Adjustable shock part number 8041-1186S. Listed by Koni for 1994-2004 solid axle-equipped Mustangs, it's also the MM-recommended rear shock for 1979-1993 Mustangs because it has an easily removable dust boot for coil-over conversion.
  • Koni Double Adjustable shock part number 8042-1134S. Listed by Koni for 1994-2004 solid axle-equipped Mustangs, it's also the MM-recommended rear shock for 1979-1993 Mustangs because it has an easily removable dust boot for coil-over conversion.
Requires shock-to-axle mounting brackets
  • If you have an MM Panhard Bar, the axle mount does double duty as the lower shock mount for the driver side. Only 1 shock-to-axle mounting bracket (MMSM-2) is required for the passenger side, and is included in the MMCO-5 kit.
  • If you don't have an MM Panhard Bar, you'll need 2 of the shock-to-axle mounting brackets (MMSM-2). Order a second bracket by selecting the "Yes, add the MMSM-2" option button above.
Does NOT fit
  • Any Koni rear shock listed for 1979-1993 Fox Mustangs. The several variations of Koni shocks built for those model years include features that make them unusable for a coil-over conversion. These features include a welded-on steel dust cover, different diameters that do not fit the MM threaded sleeve, and the requirement to remove the shock from the vehicle to adjust it.
  • Koni STR.T shocks. These have a welded-on steel dust cover, and valving too soft to control a coil-over spring.
  • Any Koni shock listed for the 1999-2004 Cobra IRS.

Click here for coil-over FAQs.

We're working on more FAQs for this product. If you have a question, please use our Contact Us page to email your question. We'll answer your question by return email, and also consider it for possible addition to this FAQ section.

Each shock series works with spring rates in a particular range. Choose your springs first, and then the damper valving choice falls into place.

How do I choose which springs to use?
In general, choose springs that provide the handling characteristics and ride quality you want from your Mustang. To determine that:

  • Decide on the performance goal for your Mustang.
  • Consider how you'll use your Mustang most of the time and optimize it for that type of driving.
  • Consider what level of ride quality you want and then decide what (if any) compromises you'll make to achieve your performance goal.

For help choosing springs, see the MM Guide to Choosing Spring Rates and Dampers.

Which dampers go with which springs?
Choose your springs first. That choice dictates the damper series selection.

See the MM Guide to Choosing Spring Rates and Dampers.

You can read Maximum Motorsports' highly detailed MMCO-5 Coil Over Kit installation instructions before purchase.