Hi guys. It's time to setup my rear end, and I have a couple of questions before doing so. What I'm trying to figure out is if there is a definitive number in inches for the spread of the rear spring hangers? I'm using a Gary Maxwell/Blackboard frame and hangers, and a so-cal rear spring (which I believe is a 40 front, I could be wrong). Searching the forums, I found that 42 1/2 seemed to be the magic number for chop top kids coupe. Has anyone else found this number to be correct as well? His being a coupe and mine being a roadster, is the weight difference significant enough to throw this measurement off? I know the other option is to remove all leafs but the main, and try to simulate load in order to achieve the correct angles of the shackles. Any ideas on how to create an accurate load? First time at this and I wanna make sure I'm going down the right path. Your help is much appreciated! Thanks! Jon P.S. I have spoken with Gary and he was gonna ask a friend, but I have yet to hear back..
Sounds like you don't got definite known parts. Don't give it a definite number. Locate the rearend, let the frame sit on it, & make control arms first. It's probally a lightweight coupe or roadster, so the rear spring aint gonna really flex, mount the center of the spring then with the shackles flat & straight TACK it to the 9" at 6"travel. Tack it cause your gonna cut it & raise or lower it after it's all done.
I have all the parts ready to go. I guess I should have also mentioned I'm using so-cals ladder bars, brackets and shackles.
shackles flat & straight TACK it leave a 6" gap & it will level out good. 40 front spring on the rear is gonna be rock hard you're gonna take out leaves. Final weld after batt./seat/gas tank/etc., everything is installed, maybe even testdrive.
You need to determine if you have a So-Cal spring, or a 40 front, on the So-Cal, the dimension I use is 44", on the 40, it is 42.5".
Marty, thank you for the info, and it's a so cal spring.. I achieved the 6" of travel, but it seems a bit high. How much lower can I anticipate the car to be after full load??
The center to center dim on the '40 front spring that I used for my coupe was 42 1/2". I see that you've used a So-Cal spring, so you should prolly use Marty's dim's on that. B*** used a '40 front spring on his Model A coupe, and is running the entire spring pack. After you add a tank full of fuel, a battery and a few tools, it all add's up... I put up some pic's of my install. The spring has only about 5 leaves in it at this time, but I have a complete set of leaves and plan to adjust the spring pack to suit...
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