Friday, August 14, 2015

1964 Merc Comet Caliente front suspension rebuild and modification

Having just recently acquired this car, I set to work on the rehabilitation. Since the engine is already out this is a good time to rebuild the original suspension. I wanted to upgrade the suspension on the whole car with some improved parts and also make some inexpensive but valuable handling modifications. Here's what I did to the front.
 I retracted the coil springs up in the shock towers with a spring compressor and removed the brakes, knuckles and upper control arms as a unit. The rest was simple unbolting.

 Original 1964 parts, except the upper ball joints had been replaced some time in the past. I've seen worse parts, but there was a lot of cracking to the rubber bushings, so I decided it's got to go.
Bulldog smiling for the camera
 
Comet with wheel wells stripped
These are the only parts I am reusing from the original front suspension.

 
                                     
All cleaned up with a fresh coat of paint. I like the original springs for the fact they they're already "settled." I cut a single coil from each to lower the front end and slightly increase the spring rate.
 

                             Inner fenders had the undercoating burned off from seam-welding.
 
Next up is drilling a new set of holes to relocate the upper control arm mount points about an inch lower than it left the factory. This is known as the "Shelby drop" and improves the car's anti-roll properties as well as the camber curve through the entire suspension travel range. This is the template I use to get the new holes exactly where they have to be.
 Here's the new holes, under the original factory holes. Note the upper control arm will be an inch lower and an eighth of an inch rearward to also improve caster. I sprayed a little fresh undercoating over the areas left bare from welding.

Here's all the fresh suspension ready to go in

 
                                             
This is the coil spring compressor I used to tuck the springs into the shock towers while installing the goods underneath.

                                       Top of compressor poking out of the right shock tower.
The bottom of the compressor bolts in place of the shock absorber to the vehicle's spring perch and the coil is compressed thusly.
 
When the spring is adequately retracted into the shock tower, I introduce the upper control arm and loosely bolt it to the spring perch.
 Then I fitted the upper control arm's pivot shaft bolts through the new "Shelby-spec" holes and tightened down all the bolts. Here's the view from inside the engine bay- this is way easier with the engine out of the way.
 

                            Next I hang the original cleaned and painted spindle/knuckle in place.
 Then the lower control arm is set in place. Note the spring compressor is still installed. I do not fully tighten the inner lower control arm bolt yet. It will be torqued to spec once the full weight of the car is on it and it is sitting at proper ride height-orientation.
 

I jacked up the lower control arm just enough  to support the force of the coil spring so I can safely remove the spring compressor.
    Once the compressor is removed a new gas-charged shock is dropped into place and bolted down. The jack is removed and the suspension is almost done.
                                     
The strut rods are reinstalled with new bushings and voila! New upgraded suspension at the front. Unfortunately, I received an incorrect sway bar so I was unable to install one as of these pictures. I ordered a 1" and they sent a 3/4 inch. A proper 1" bar is forthcoming to complete the front upgrade.