Product Summary

Universal Fit

  • Works with all Speedway and Heidt's Mustang II crossmembers
  • Air ride bags with the proper adapters, shocks, and weld on shock brackets are included
  • Features 5/8" narrower tubular control arms reducing the track width to 1.25" overall allowing more room between tire and fender
  • Wilwood 10-3/4" brake kit is utilized to gain clearance for air ride components and gain massive stopping power
  • 2" dropped Mustang II spindles are used to get maximum drop allowing you to air down the suspension into the weeds!

Key Specs

MFG. Part #
BrandSpeedway Motors

Need To Know

Quick and Easy Returns

Return Policy


Hub-to-hub kit includes 5/8" narrower upper and offset strutless lower control arms, 2" dropped spindles, rubber brake lines, air ride , new manual or rebuilt power rack & pinion with bushings and new tie rods. The 10-3/4" Wilwood brake kit features GM Metric calipers with rubber hoses, with your choice of 5 x 4-1/2" or 5 x 4-3/4" bolt pattern.

  • Works with all Speedway and Heidts crossmembers 
  • Kit Includes:
    • 5/8" narrower Tubular Upper and Lower Strutless Control Arms
    • 2" Dropped Spindles
    • Air Ride Suspension shocks
    • Rack and Pinion with bushings and tie rods
    • 10-3/4" Wilwood brake kit with GM calipers
  • Add proper crossmember to complete kit - Must include Mustang II crossmember for complete installation (sold separately)

Note:  OEM rubber brake hoses generally cannot be adapted to Wilwood calipers. The caliper inlet fitting is a 1/8-27 NPT. The preferred method is to use steel adapter fittings at the caliper, either straight, 45 or 90 degree and enough steel braided line to allow for full suspension travel and turning radius, lock to lock.

Note:  If using these kits with Speedway or Heidts crossmembers for 1948-1956 Ford Pickups, 1955-1959 Chevy Pickups, or universal crossmembers for 27-1/2" - 33-1/2" frame widths, you will be required to purchase 2" Inner Tie Rod Extensions (91034345) or (91034346).



  • Minimum Wheel Diameter (in): 15"
  • Wheel Stud Diameter: 1/2"-20
  • Caliper inlet fitting: 1/8"-27 NPT
Hub-to-Hub Kit (Less Crossmember)
  1. Tubular Upper Control Arms
  2. Tubular No-Strut Lower Control Arm
  3. New Stock or 2" Dropped Spindles
  4. New Air Springs
  5. New Shocks
  6. New Manual or Power Rack & Pinion
  7. New Tie Rod Ends
  8. New 11" Brake Kit
  9. 5x4-1/2" or 5x4-3/4" Bolt Circle



The original intent of the air spring was to provide a very smooth ride.  It was not designed to provide an adjustable ride height.  You can not drive the vehicle at any ride height you select. 

All suspension systems are designed to operate at a specific midpoint position, with provisions for suspension travel. The Mustang II suspension is no exception. It has a specific mid-point position which is when the lower control arms are level. The suspension must be in this position to provide full suspension travel and correct geometry action.

In this type of suspension the shock is normally the bottom out device. When the vehicle is lowered the shocks compression and extension limits change and the shocks will bottom out or the ball joints could pinch when it is lowered. The air ride suspension is only designed to lower your vehicle while it is parked. If you attempt to drive a vehicle in the lowered position it could be dangerous and will cause damage to your vehicle. This could result in broken control arms, shocks and ball joints.


MFG. Part #
BrandSpeedway Motors