Transverse Arch Spring

[Tjbucket]

Ok, so now that my car is re-build I see a major problem and have searched for the correct answer but have came up empty......and know someone here can assist. My rear spring is a medium arch transverse leaf, nothing changed as far as that goes from what was originally on it when I got it, but, that does not mean it was correct from the get go. From everything I have read the shackles should be at a 45 degree angle or there about once mounted. Mine on one side is and the other side sits with too much slack. So, I have been searching to find out how to measure what size spring I need but, everything I find speaks about the spring length and not the distance between the mounts. Is there a way to determine spring length from how far apart your mounts are? My mounts are at 46 1/2 center to center.

 

[choppedtop]

Best I can find...measure center to center on your mount, then deduct 3 inches for proper spring length, eye to eye. Do you have a panhard bar to keep things equal? May not be needed, but it sure can't hurt.

 

[HenrysT]

pics would be nice, but the easiest would be to get shorter shackles. I don't know what your shackle length is but most shackle distance is 1 1/2" c/c. For the front, the spring should be 5" shorter than the bat wings.

 

[tfeverfred]

Best I can find...measure center to center on your mount, then deduct 3 inches for proper spring length, eye to eye. Do you have a panhard bar to keep things equal? May not be needed, but it sure can't hurt.

If you're running a rear transverse spring, you don't need a panhard bar.

46 1/2" seems a lot. Take a look at Speedways medium spring.
Medium Arch Transverse Rear Leaf Spring, Reverse Eye, 38 Inch

Here's Speedways spec chart.
http://static.speedwaymotors.com/images/charts/91043105.gif

High arch chart
http://static.speedwaymotors.com/images/charts/91043102.gif

 

[old round fart]

Shackles should center themselves. Do the shackles bind? Is the car level? What happens when you bounce on the back of the car? Are the spring eyes the same distance from the ground? Like they say.......... Pix help!

 

[Tjbucket]

Here you go....see the left side, is not right. The spring is too long.

 

[Tjbucket]

To add to that, when I assembled the spring to the rear end, it seemed to fit correctly. But, now that the weight is on it seems to have shifted. Sorry not the greatest pic, but will give you a better idea what is going on.

 

[old round fart]

I have never seen a spring do that. Unless there is a bind the shackles should hang at the same angle.

 

[JeffK]

Just a thought, both mount points on the axle tube seem to be the same in relation to the hub, It appears the axle is a 9" centered, could the distance from the center of the perch to the actual axle bracket be different lengths. Seems that the longer tube axle bracket would need to be further away from the hub. Drop a plumb bob from the center of the perch and measure out to the mounts, should be the same distance..

 

[2old2fast]

Spring is too long , when you assembled the spring you should of had to use a spreader to hook up the shackles . A "good" spring shop should be able to re-roll the eyes to shorten the spring , otherwise you'll have to find 1 the right length , talk to different spring suppliers , they should be able to tell you how to measure for the correct length..
dave

 

[JeffK]

Also check your rear from center to the inside of frame rails, I see a panhard in there, it may need tweaking

 

[old round fart]

If there is a pan hard bar, disconnect it and see if that helps. That would be the bind I was looking for!

 

[kookie2007]

Just a thought, the pan hard rod is on too much of an angle. If it's even needed it should be as close to level as possible. As it is, it's actually pushing the frame to the left as more weight is put on the car causing the shackles to go off center. I agree with ORF, disconnect it and see what happens.

 

[JeffK]

** I am assuming (I know, right?) that is a panhard mount at the 2 o'clock position on the pumpkin...

 

[Tjbucket]

Spring is too long , when you assembled the spring you should of had to use a spreader to hook up the shackles . A "good" spring shop should be able to re-roll the eyes to shorten the spring , otherwise you'll have to find 1 the right length , talk to different spring suppliers , they should be able to tell you how to measure for the correct length..
dave

Yes, I did have to spread the spring when I assembled it. Fought like hell to get shackles together. Like I said it was fine until I put it under the car. Now when I think about it the left side was lower (slightly when I bought it). I did a bunch of stuff different, but, didn't really change that much other than add a lot of chrome......I like shinny things. Now it has the same lean to the left as it did before. Looking at it today.....I think I can remove the bottom 2 leafs have a spring shop hopefully cut and re-roll the ends and shorten up the second leaf and be GTG. Need to find a local spring shop and run it by them. Thanks for everyones help on this. Like I have said in other posts.....this is my first street rod rebuild and there has been a lot of doing and re-doing. Guess that is how we learn.....well at least that is how I learn. Reading only takes you so far.....

 

[Tjbucket]

Just a thought, the pan hard rod is on too much of an angle. If it's even needed it should be as close to level as possible. As it is, it's actually pushing the frame to the left as more weight is put on the car causing the shackles to go off center. I agree with ORF, disconnect it and see what happens.

I will give it a shot, at this point. Nothing to lose. I have a sneaking suspicion that is not the problem.....but, hell I am game. Not much to rule that out.

 

[Tjbucket]

** I am assuming (I know, right?) that is a panhard mount at the 2 o'clock position on the pumpkin...

Jeff,
Yes it is......good observation, didn't think anyone would pick that up. However, If you read a couple post I just submitted, the car leaned to the left when I bought it. I figured after all the changes I did, it was corrected and overlooked the spring. The spring is just plain too long, I will disconnect the pan hard bar to rule that out though first.

 

[2old2fast]

The only other thing I can think of is the arc of the spring , ie; if the left side doen't have as much arch as the right , that could "possibly" throw things off...
dave
just for giggles ,could you post some pics of the suspension ,frt & rear ?

Ihave another thought , but I'll wait 'till I can see the rest

 

[2old2fast]

'"Just did some reading , seems this "leaning" thing is alot more prevalant than I thought, cures ranged from 1. loosen the spring u bolts , rock the car till it sits level , then tighten the u bolts evenly & see if that helps 2.switch spring around 180* & see if that helps. 3 make sure both sides are the same by laying it on the floor & tracing on floor , then flop the spring over to compare ..4. use wedges between the spring & crossmember ...
dave

 

[JeffK]

Jeff,
Yes it is......good observation, didn't think anyone would pick that up. However, If you read a couple post I just submitted, the car leaned to the left when I bought it. I figured after all the changes I did, it was corrected and overlooked the spring. The spring is just plain too long, I will disconnect the pan hard bar to rule that out though first.

Glad you are making some headway into your issue. Hopefully you get it fixed soon, warm weather is coming !