Project 53 Bel Air

[tterbo]

I got a little more time to work on the front crossmember and suspension this past weekend and it is finally starting to look like something. After using what felt like half a roll of welding wire I got the front crossmember welded up and tacked into position on the frame rails. Since my wheel position is fixed, the lower control arm mounts pretty much "self-position" front-to-back once my target caster setting is established.

Then I took some 1-3/8" x 1/4" wall DOM tubing for the lower A-arm mounts. I had these 14mm threaded inserts that just so happened to fit snugly into the tube which worked out nicely as they have a large thrust flange for the bushings.





With the lower A-arm positioned I started figuring out how to mount the upper A-arm and coil-over. The upper arm mounts at an angle tilting upward back-to-front, around 6-7 degrees. This matches the OE caster angles of the spindle which is where I am setting the center of my caster adjustment. I designed an upper A-arm mount with slotted holes to allow extra caster adjustment. Once I cut out the plate and put it in place I realized that I was going to have a problem getting negative camber. The C5 suspension forced the frame rails to be narrower than I was expecting so I cheated it a little by offsetting the A-arm mounts inward to keep my frame rails as wide as possible. It was easy to do on the lower A-arm mounts but the uppers are hanging the mounts off the frame rail on the inboard side of the rail. After spending too much time trying to figure out how to make an offset upper mount I came up with an easier solution. If I mount the arms on the inside of the mounts instead of the outside I have all the camber adjustment I need. The only problem was the mounting shafts in the bushings. I would have to slide them through the mount then weld the mount in place which would make the arms unserviceable and "locked" onto the frame. The easy solution to this was to order a set of Delrin upper bushings. Companies like ridetech, Van Steel, and Pfadts make them so the inner mounting shaft easily comes out by removing a C-clip. This will allow me to slide the arm through the mount and then install the mounting shafts. And of course it will also eliminate the deflection in the upper A-arms by removing the soft rubber bushings. I will probably upgrade all of the bushings to Delrin eventually.



That's as far as I got but hopefully I will have some upper A-arms and coil-overs mounted soon then on to the rack mount!