Rear springs arched differently

[mrwfp]

I purchased a pair of Mopar performance rear leaf springs.  The right rear spring (P4452984) was stamped "made in Mexico". The left rear spring (P4452985)was not.  While I understand that the leaf configuration is different between the left and right springs, when put side by side, the left spring is arched about one inch higher than the right spring.  Is this correct or is the right side one made in Mexico too flat?

[70chall440]

The "made in Mexico" part isn't a concern as Chrysler and many others have been making stuff there for many years. The arch part however seems wrong, they should look the same when side by side. It could be you have a super stock spring and a regular spring.

[mrwfp]

Thank you for the reply. I ordered the Mopar HD rear springs with the part numbers shown in my opening text.  Those numbers are stenciled on the springs as well as on the part tag of each spring so they are the same springs of a pair and not two different types.  While only one is stenciled "Made in Mexico" the part tags on each indicate made in Mexico.  The source is not an issue only the difference in the arch.  This morning I saw that someone else had asked the same question on another forum and the response was that they would be arched differently and the responder stated that they came from the factory that way back in 1970. And yes, the left rear of the car will sit higher than the right and the right front lower that the left front due to this. The responder claims that adjusting the torsion bars in the front can compensate for this difference. I have no issue tweaking the torsion bars other than that will change the camber and toe in of the right side that is raised to compensate for the tilt. I have also emailed the vendor and asked the same question but have not yet had a response.

[70chall440]

I don't know who those people are but you should not have to adjust the T bars to compensate for the leaf spring arch IMO. I have sets of springs in my shop (factory and Hotchkiss) and they seem to have the same arch as their counter part. Of course I could be wrong.

[mrwfp]

I appreciate your response and I am hoping to hear from the vendor about this. I was planning to install these once I received them but I don't want to install something where a mistake may have been made and I have to undo everything. But maybe there isn't a problem. I just measured both springs. One has an arch of 7 1/8 inches floor to the spring bottom at the center mounting point, the other is 6 1/2 inches from floor to the same point.  However, when laid side by side, the spring with the greater arch is 1/2 inch shorter. If I press down on that spring so that the arches are about the same, the lengths are even. So, this extra arch will probably flatten out as it is installed since the lengths on both sides from the front mounting points on the car to the rear shackles should be the same.

[jimynick]

I have SS springs in my Challenger and the rt one has an extra leaf. Couldn't the higher left spring be arched so that when the load is on, that the higher initial set matches the lower, but stiffer right and loads the diff equally? What other reason is there?? 

[mrwfp]

I installed them yesterday. Took about 3 hours. I measured all 4 corners before and after and they is no significant height difference due to the difference in arches.  All 4 corners are within a 1/4 inch of each other all the way around.
 

[jimynick]

There ya go! All's well that ends well. 

[70chall440]

I agree.

AS a point of interest I am currently doing some research on rear suspension (specifically how to make it handle as well as possible while keep leaf springs) and I have a set of springs off my 71 Charger and a brand new set of springs from Hotchkis for another project, neither has one spring arched more than the other.