My original rear swaybar attempt is pictured next to the car.
As you can see the length of wire between ball end and bend on each side is longer on the standalone swaybar. This is to account for the extra reach needed to achieve a “right angle fit” when the ball stud mounted on the rear A-arm is pointing towards the rear. Using my physics knowledge gained from a very knowledgeable and talented high school physics teacher I concluded that, all else such as wire thickness being equal, the swaybar mounted on car currently (with balls pointing forward) is stiffer. The stiffness of the swaybar is partially due to the total angle by which the bar in the middle has to bend or rotate. Because the translation distance of the ball stud on A-arm during suspension travel is equal whether it sits pointing forwards or backwards, the shorter side lengths of the current swaybar result in a greater arc of rotation in the bar when one wheel is fully up and other is fully down. Furthermore, the mechanical advantage in torquing the bar is greater when the sides of the bar are longer (put another way – the bar exerts more force at the ball ends if the sides are short, assuming torque on bar is the same). In other words, if you want to soften the rear swaybar you can either choose a thinner wire material or you can use the same gauge wire but lengthen the side pieces between bend and ball end on piano wire.
My first attempt at soldering the original rear swaybar took a long time but resulted in a fairly nice swaybar. The hardest part was getting the ball on the rod straight. I had to use many tries before finally getting it straight. I imagined myself soldering a 14 gauge wire onto a 3.5 mm bullet connector. The same challenge exists there – namely to get the bullet connector to sit straight on the wire. Then, there was solder residue on the ball end. It didn’t look professional. I tried to wipe as much of it off as I could with the soldering iron without melting the current position the ball was in. Finally I took a file and made the six sides of the hexagon smooth again. Unfortunately on my original bar I took off quite a bit of the black coating that was on the ball end with the file. So the balls look silver both because solder got onto them and because the black coating was partially filed away.
At some point of the soldering process I smelled what seemed to be CA glue vapors. I recalled that I tried gluing a swaybar together in my youth after failing to solder it. I was using some of these thirty year old ball ends that had been sitting in the drawer. I continued pouring and boiling flux into the ball end hole and I continued melting solder into this hole until I could smell no more of these vapors.
The second rear swaybar was more of a success as was the front swaybar. But again I faced the same problems: getting the hex ball ends on straight and finishing them to look professional. I think that a little bit of solder on the ball ends and taking a little bit of black coating off is as good as it gets, and is expected on these cars from the 80s.
The rear bulkhead clearly has a groove made for accepting a swaybar. The notches at the edges of this groove even match the style and nature of the notches at the edges of the grooves found in the front suspension mounts, which are intended for exactly that purpose, namely to delicately cradle a swaybar.
The front swaybar cups (the clear plastic DU-BRO parts) were cut to be shorter using a Dremel tool. In photo you can see them bottoming out against each other, meaning that this turnbuckle link cannot be shortened any further. My original approach was to shorten the cups before even trying the original length of ball cup. This hunch proved to be correct. Right now the length of the link is close to optimal when examining the front swaybar angles as the suspension moves. With the original plastic cup length the link would have been about 1 cm longer than now.
One of the photos shows front swaybar instructions found in original Edinger manual. No mention of rear swaybar is made.
The threaded connecting rod used between plastic swaybar ball cups is #2-56 connecting rod, also called threaded stud. It’s made of aluminum and isn’t exceptionally strong. I assume that it’s 6061-T6. It’s strong enough for its purpose – these swaybar parts don’t get a lot of stress (unless there’s a collision with another car or unless there is the act of hitting something stationary, resulting in direct impact to the part). The aluminum connecting rods can be ordered from a supplier such as McMaster-Carr. A 7075-T6 or titanium grade 5 connecting rod would have been more ideal but was not found. I’ve had a hard time finding even strong steel threaded rod in these small sizes.
(Continued in next post.)
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