Very irritating!!

['74 Sport]

While he was home for the weekend, Aaron and I thought we would get some work done on his Duster project. I had bought some new leaf spring bushings, and we were going to install them.

I had contacted Energy Suspension to have them help me determine the correct bushing set for some super stock springs Aaron bought a while ago. I provided measurements for the front spring eyes, because they are smaller than the stock springs, with a smaller bolt also being used.

They told me which kit to buy for super stock springs and I did so (through another vendor for less than their price). Little did I know that I should have also given measurements for the shackles while I was at it. As luck would have it, the darned bushings in their kit for the shackles were too large. They are 1" diameter, but the openings in the springs are only 7/8".

Due to their appearance, these SS springs are probably older ones (significant pitting due to rust). Therein lies the question: did the rear eyes on SS springs change over the years to a larger 1" diameter? Anyone have a new set lying around that can be measured?

The front bushings fit perfectly, so maybe they can tell me if they have other sizes available for the rear.

Any help is appreciated,
Jerry

 

['74 Sport]

This is getting, as Alice in Wonderland would say, "curiouser and curiouser". I am at a complete loss, now, and need some clear understanding of what is going on with Aaron's leaf springs. The following pictures show stock '74 Duster springs we are replacing and the set of "super stock" springs that Aaron bought a while ago for the project.

As you can see, the stock springs have five leaves, 2" front eyes (with bushings for 5/8" bolts), and 7/8" rear eyes (with bushings for 1/2" shackle bolts). The springs sold to Aaron as "super stock" are the exact same length, have only four leaves, but have the exact same arch when laid on top of the stock springs, have smaller 1-1/2" front eyes (with bushings for 1/2" bolts), and the same 7/8" rear eyes (with bushings for 1/2" shackle bolts).

I purchased a 5.2104 bushing kit on the recommendation of Energy Suspension's technical support, for "440, 426, and super stock" applications. The kit has 1-1/2" front eye bushings with 5/8" bolt sleeves (yeah!). However, the rear shackle bushings are larger 1" (not 7/8") and have 1/2" shackle bolt holes. Close, but no cigar.

I'm guessing I can probably work out the bushing issue, but what doesn't add up and is confusing the situation is the similarities between the two sets of springs. I suppose I first need to better understand what exactly "super stock" springs are. I had thought they would be "beefier" with either more arch, more leaves, or thicker leaves to give a stiffer ride. I was told that a set of true "super stock" springs would leave the car a bit higher on the right side because of the extra leaf to resist the torque of a hard launch.

Would some of you who have a good handle on "super stock" springs please explain what we have and is there really any advantage to using them? By the way, I have not been able to find any numbers stamped into either set of springs, so that is not going to help.

Thanks for any help,
Jerry