Monday, October 7, 2013

Rear Coilover 4-Link Suspension

The rear ride height of my Mustang was a little high for the look that I like. I thought about installing some lowering blocks but wanted something more modern with a little better performance.  After researching a few rear suspension options, I decided to update to a coil-over suspension and install a suspension kit. Combined with the front coilover suspension, the end result will be a classic street machine that handles more like a modern sports car. 

I decided to go with a bolt-on kit from TCI.  Considering that many vintage race cars run factory style leaf springs and lots of people race with that kind of set up and have few failures, I didnt see the need for a full on competition suspension kit.  Bolt-on works well in a factory leaf spring style setup so a beefed up bolt-on 4-link system should work well too - albeit less sexy than a pre-welded Fab-9 or Moser setup.

Weld-on brackets
Once the old setup was out I could begin mounting the new control arm brackets.

The upper control arm brackets are welded to the axle tubes at specific locations, centered between the axle flanges.  A jig is provided for exact placement. A heavy duty welder is needed as the brackets and tubes are pretty thick metal. 

 The lower control arms bolt to brackets that get bolted to the existing spring perches.  If you have Ford 9 inch with 3" tubes then you can cut off the stock perches and weld on brackets like most of the beefed up kits use.  My housing has tubes that taper to 2 13/16 (2.8125) inch diameter so there would be a lot of slop to fill in the 3 inch holes. I went with the bolt-on brackets and did a couple welds for extra insurance.  

Powder Coat
Once everything was welded and ground, I dropped the housing and kit pieces off at the powder coat shop.  At the powder coater, they cleaned and media blasted everything and applied a custom metallic gunmetal on the housing and metallic silver on the control arms, sway bar, and crossmember.  The frame brackets were powder coated in chassis black to match the existing metal.

After drilling holes in the frame rails and floor at the prescribed locations, the chassis brackets are bolted on.  The kit also provides thick reinforcement plates that bolt to the opposite side of the brackets.

With the brackets in place, it was just a matter of positioning the housing and bolting in the control arms.  This was followed by installation of the center section, the axles, and the drive shaft.