Yep, if you look below the spring perch you will notice a bolt going through both the perch (tied to the springs) and that leads to the actual mount that is welded to the axle housing. This is called a leaf spring pivot and you are correct...this wouldn't work (or things would bind) if these weren't utilized. There are different types of these devices, but I can assure you that they are there on 'Olerodder's rear from the pictures. His car is set up nice!
MNTony, Thanks for the more indepth explanation. Also, you can switch the bolt from the top hole in the Pivot brack and put it in the second hole, this will change the angle. This setup is over 30 years old and was actually introduced in the in the SS/SM ranks in the late 70's when Chrysler/Dodge came out with it. Cam1000, Since the car is up on jack stands I will try and get one tire off this weekend and take a picture..............taking the slicks off is a "real pain", but I will do it just for you.
Why not use a Watts link? Leaf springs are lousy at holding side to side position. I am all for long ladder bars with a pivot mount for the leaf springs but it needs a Watts link to lock the differential in the center.
I have run "Watts Linkage" and Pan Hard Bar setups on my Mustang Cobra...................the watts linkage worked great and you could change the "roll center" of the car which was neat for doing experimenting. The car had other suspension mod's also and it came close to that magic 1G on the skid pad, but was not terrific to drive on the street. The draw back to a well designed watts linkage is that it takes up a lot of room, and you have to calculate and know where the roll center of the car is and how to setup the linkage.........................if not................the watts linkage can send you into the weeds or worse! Everything on the linkage has to parallel (the two outboard arms) and the center pivot needs be dead on perpendicular to the ground. As for the panhard bar, I actually punched a whole through the trunk section where it mounted to the body, and after repairing that (and also reinforcing it), then I proceeded to bend the panhard bar itself. I was told (by the manufacturer) that I set up the panhard bar wrong and that I should have adjusted it under load and made sure I could move the bar by hand (twist it back and forth on the right and left hand threads before I locked it down with lock nuts on either end) and everything time I set it up as they told me to but always bent the bar and very hard cornering.......................so I went to watts linkage and never had any further problems. So, although I would certainly use a Watts Linkage if I had the room, on the street I am not sure I would try either for drag racing..........although I know some people with fast cars use them. IMHO
I have always mounted the center belcrank to the differential housing. That does away with the big problems of having a framework that takes all that room. Once the center bellcrank is mounted you just have to install "down legs of the appropriate length to have the links parallel to each other and the ground at the height you desire. I set mine with a 200 pound load in the trunk so it is "neutral" under moderate acceleration. With the pivot of the bellcrank at axle centerline. I never liked panhard bers because they force the rear end to one side or the other depending on the length of the bar and where it pivots in relation to the center line of the axle. Although ladder bars are frowned upon in road racing I like the over-steer that comes with them and find it controlable and even find security in those situations. You have to find some way to limit spring wrap-up or torque twist in the rear axle if you are going to use the Watts linkage - I guess I just prefer the ladder bars over anything else.
