Help needed on MP Leaf Springs Fitment Advice

[valman]

I have installed my leaf springs on my 70 Challenger restoration thinking they were original but now realise they were swapped at sometime. After searching the part # I've found them to be Mopar Performance competition springs that are not recommended for street use.Why?? Here in Australia it's very hard to find the originals and they worked fine for the years I drove it before I restored it. The problem is the angle on the rear shackels look wrong and yes I have the L/R springs mounted correctly. Are there different shackels I need to use with these springs?
I can't remember what the angle was before I removed them but I don't think they were that obvious,should the shackels be swapped around? hoping someone can help...

[Cuda Cody]

What axle are you using?

[Cuda Cody]

It almost looks like the location of your U bolts or axle is off?  Do you recall if the leaf springs looked straight before you put them in?  The leaf springs only have 3 points they connect at.  The front, back and of course the axle.  Those should all be lined up.  Has your axle been modified?  Was there any body work done to the car when it was painted?

[valman]

Its the factory Dana 60, the springs looked straight when they were out when i painted them and yes plenty of body work but just the trunk and floor pans the chassis rails remained original from the rear torque boxes through to the back.

[Brads70]

What is the measurement of the spring pads on the rear end, center to center?

[valman]

What is the measurement of the spring pads on the rear end, center to center?

I will measure them tommorow

[dodj]

Its the factory Dana 60, the springs looked straight when they were out when i painted them and yes plenty of body work but just the trunk and floor pans the chassis rails remained original from the rear torque boxes through to the back.

If the axle spring perches are correct...maybe the frame rails too far apart/lined up correctly  following trunk pan replacement? 

[Cuda Cody]

Also measure the distance apart the frame rails are at the point the rear leaf springs attached.

Its the factory Dana 60, the springs looked straight when they were out when i painted them and yes plenty of body work but just the trunk and floor pans the chassis rails remained original from the rear torque boxes through to the back.

[Brads70]

What is the measurement of the spring pads on the rear end, center to center?

I will measure them tommorow

Have you had that Dana in the car before? I wonder if it was from a B-Body?

[HP2]

Those springs are 3800# units for 64-65 Plymouth Super Stock cars. I suspect someone used them for your car because of the weight rating. These can be used on the street, but Mopar did not suggest it because they are/were a very high bias competition spring with a lot of leaves with a very high spring rate that will ride considerably firmer than stock.

The front hangers should also be two inches longer than stock. Also, the super stock set up was designed to make the springs sit in the car parallel to the centerline. This is what you are seeing here. Someone used stock E body shackles where they should have used offset shackles because the springs are no longer splayed. In factory form, the springs mount wider at the rear. I suspect you never noticed these before because the valance was mounted in place and hide them. Yes, they will still pivot back and forth and function as shown. They will wear out the rubber bushings faster this way.


I think the easiest thing to do would be to simply install offset shackles. Google Mopar offset shackle and you will see plenty of examples of these. They are often for sale on the web. Since you are in Aus, you may be able to source some closer to you as there are a fair number of Mopar guys there.

[valman]

Thanks HP2 you are spot on with your answer. I will look for offset shackles now I know they can stay on the car for street use. And yes the front hangers are larger than stock ones with 2 settings.

[Cuda Cody]

Right on @HP2   

[MoparLeo]

46" between the perches is stock.

http://www.moparts.org/Tech/Archive/axle/16.html