Help with leaf spring selection,

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Thanks 72bluNblu I was hoping you would chime in. I think I will go wih the P4529415 springs with the +1 arch to give a very subtle rake, the price is right and no shipping costs involved. For a rear sway bar I would like to go with one that mounts into the spring perches but not sure if one is made for a 1/2" offset hanger set up. Do you know of anything that works with that? My biggest limiting factor will be 15" rubber for my steel wheels and dog dish caps. Fronts are 15x6, rear are 15x8. Any suggestions for rubber?

There aren't a ton of frame hung rear sway bar options out there to begin with. Obviously the stock ones are, but then you're stuck with stock diameters. Firm Feel sells one, but I have no idea if they can adjust that for a 1/2" spring offset or if the 1/2" offset is really even enough to be an issue. I'm sure if you called Dick at Firm Feel he could tell you. Most of the aftermarket bars are hung from the rear axle (Hotchkis, Hellwig, Adco, PST) and for those the 1/2" offset isn't really enough to make sway bar mounting a big problem. I actually use the Hellwig E-body rear sway bar, #6908, which is a solid 7/8" bar. Hotchkis sells a set of studs for the rear dog bones if clearance to the springs is a problem. https://www.summitracing.com/parts/hss-17366/overview/

As far as tires go, I'm not really sure what you tell you. Selection for 15" rims pretty much drops to BFG T/A's and Cooper Cobra's once you go wider than a 225. I had a set of Falken Ziex's on my Duster when I was running cop rims, they were 225/60/15's. But once you go to a 235, 245 or larger all that's left for options are the T/A and Cobra's. They're "OK", but neither is designed for real performance handling.

And you may want to figure out your tires before you go to a +1" spring. It may not look like it, but my car actually has about a 1/2" rake front to rear. Pretty much all from the difference in tire height, I have 25.6" tall front tires and 26.1" tall rears. I assume you're running the 1/2" spring offset to run wider tires in the back, but with the tire selection available in 15" rims that means your rear tires will probably be more than a little bit taller with the fronts, especially with only a 15x6" wide rim up front. You may get more than enough "rubber rake" to not need any additional rake from your springs.

Oh, and the rear bushings you'll need for the 1" rear eye on those springs are these guys. https://www.summitracing.com/parts/ens-2-2117g. You'll still need the standard A-body bushings for the shackle to frame mount though.

Im running the 120lb circle track springs with the ar front hangers, works great and the steel seems thick enough with the 4 leafs, wish they were constructed a little better but for the price they are a good deal. Weather kind of sucks right now so i cant get a good pic.

Not sure how they're supposed to be "constructed better". The number of leafs isn't as important as the rate and balance between the front and rear sections, and the 120 lb/in rate is higher than the stock A-body XHD springs.
 
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As far as tires go, I'm not really sure what you tell you. Selection for 15" rims pretty much drops to BFG T/A's and Cooper Cobra's once you go wider than a 225. I had a set of Falken Ziex's on my Duster when I was running cop rims, they were 225/60/15's. But once you go to a 235, 245 or larger all that's left for options are the T/A and Cobra's. They're "OK", but neither is designed for real performance handling.
I might look at the Mickey Thompson sportsman SR tires, they have all common 15" sizes.
How critical do you think having a rear sway bar is with my tire limitations?
 
I might look at the Mickey Thompson sportsman SR tires, they have all common 15" sizes.
How critical do you think having a rear sway bar is with my tire limitations?

Not sure how the Mickey Thompson's stack up, I haven't run a set and they don't publish their treadwear numbers to get an idea of how soft those compounds are. And TireRack doesn't carry them so no testing reviews either. Although it would be difficult for them to be worse than BFG T/A's for handling. This is why pretty much all the performance handling cars go to 17" wheels (or larger).

As far as the sway bar goes, I still think you'd be better off with a front and rear bar, even if they're just stock pieces. I don't think they're critical unless you're planning on pushing the handling pretty hard, but they'll definitely help. One thing I wouldn't do is run a front sway bar without a rear sway bar with that set up. Either run both or none at all, at least to start off. Yes, the factory offered these cars with just a front sway bar, but the front suspension of these cars was also massively undersprung from the factory. The rear suspension, especially with the XHD's, was not nearly as undersprung as the front. So adding a factory sway bar to the front suspension with the stock torsion bars would still leave the car undersprung in the front. Better, but still undersprung. Going to 1.03" torsion bars in the front goes a long way toward evening up the spring rates, so running a front sway bar without a rear could unbalance things. It does depend on your set up, which includes things like how much the car is raked, how much the tires are staggered, etc. But if you're not going to run a rear bar to start off with I would start without a front bar as well, see how it handles, and then go from there.
 
There aren't a ton of frame hung rear sway bar options out there to begin with. Obviously the stock ones are, but then you're stuck with stock diameters. Firm Feel sells one, but I have no idea if they can adjust that for a 1/2" spring offset or if the 1/2" offset is really even enough to be an issue. I'm sure if you called Dick at Firm Feel he could tell you. Most of the aftermarket bars are hung from the rear axle (Hotchkis, Hellwig, Adco, PST) and for those the 1/2" offset isn't really enough to make sway bar mounting a big problem. I actually use the Hellwig E-body rear sway bar, #6908, which is a solid 7/8" bar. Hotchkis sells a set of studs for the rear dog bones if clearance to the springs is a problem. https://www.summitracing.com/parts/hss-17366/overview/

As far as tires go, I'm not really sure what you tell you. Selection for 15" rims pretty much drops to BFG T/A's and Cooper Cobra's once you go wider than a 225. I had a set of Falken Ziex's on my Duster when I was running cop rims, they were 225/60/15's. But once you go to a 235, 245 or larger all that's left for options are the T/A and Cobra's. They're "OK", but neither is designed for real performance handling.

And you may want to figure out your tires before you go to a +1" spring. It may not look like it, but my car actually has about a 1/2" rake front to rear. Pretty much all from the difference in tire height, I have 25.6" tall front tires and 26.1" tall rears. I assume you're running the 1/2" spring offset to run wider tires in the back, but with the tire selection available in 15" rims that means your rear tires will probably be more than a little bit taller with the fronts, especially with only a 15x6" wide rim up front. You may get more than enough "rubber rake" to not need any additional rake from your springs.

Oh, and the rear bushings you'll need for the 1" rear eye on those springs are these guys. https://www.summitracing.com/parts/ens-2-2117g. You'll still need the standard A-body bushings for the shackle to frame mount though.



Not sure how they're supposed to be "constructed better". The number of leafs isn't as important as the rate and balance between the front and rear sections, and the 120 lb/in rate is higher than the stock A-body XHD springs.

What I meant about the construction i didn't mention in my reply. The paint job could be better and one of my leafs is wider than the others on my drivers side by about 1/4" so I lose a little tire to leaf spring clearance and from what I remember when I put them in one of the eye holes wasn't consistent in its sizing between the two leafs. I believe I had to take some bushing material off on my poly bushings so that it would fit, but even after all that for the price I'm happy with them.
 
I can say that I have always run MT's on both of my darts. I'd be hard pressed to change that. I've also run their new radials on a 40 ford pickup. I've run their tires on my diesel trucks too. Love MT and have NEVER been disappointed.
 
Well I have now ordered the Mopar Performance p4529415 springs, they should arrive in the next day or so. I will let you all know how they are. I also ordered the Hellwig rear bar to compliment the springs.
 
Glad I found this thread I currently have a homemade bastard pack for the leaves in my '70 Duster but I'd prefer to have a brand new set with the proper known rates at some point.
 
Did you order the sway bar local or out of the States?
 
FYI I purchased the xhd mopar leaf springs some time ago. There is a left and right part #. Right side ends up higher than left!:wtf:so ended up with 2 left side springs to be nice & even!
 
My new Mopar Performance leaf springs are installed. I used the correct aftermarket hangers designed for these springs which are shorter to accommodate for the 20.5" front segment. I used the upper eye on the hangers to give the lowest stance with the spring. I installed 1/8" alignment plates in front of hanger for a little more tire clearance, I really like how it looks with my 28" tires. The rear end of car at wheelwell is 1 1/8" taller than with my split leaf Cal Trac stock ride height springs. I expect springs will settle out a little in time. One thing I noticed is my pinion is now pointed upward quite a bit so I will be needing wedge shims to correct this. There is also very little weight on car right now as fuel tank and spare tire are out as well as engine and transmission.

I was very pleased with fit and finish of springs, mine were dimensionally identical and paint work and finish is quite nice. So far I am pleased with results.
 
Im running the 120lb circle track springs with the ar front hangers, works great and the steel seems thick enough with the 4 leafs, wish they were constructed a little better but for the price they are a good deal. Weather kind of sucks right now so i cant get a good pic.
Do you have pics of your springs? I just installed mine and they do not look right, have an s bend in front segment. This is throwing my pinion angle way out of whack also. Can't imagine what will happen to them under power. Car has not been driven and has no fuel in tank.
20170701_202925.jpg
 
Whoa, that indicates a worn spring!
I don't care if there new. That ain't right. When they look like that under acceleration, it's time to replace them.
 
Whoa, that indicates a worn spring!
I don't care if there new. That ain't right. When they look like that under acceleration, it's time to replace them.
I agree, looks like a sacked out old spring from a high powered car. Frustrating for sure, don't even have the weight of fuel in it.
 
Have you rolled the car on them yet? Did you tighten the eye bolts with the rear hanging down or all the cars weight on the rear? You might try loosening the 3 eye bolts and letting it settle.
 
Have you rolled the car on them yet? Did you tighten the eye bolts with the rear hanging down or all the cars weight on the rear? You might try loosening the 3 eye bolts and letting it settle.
I've just been out to garage and lifted frame of car allowing rear end to hang. I then loosened all the fasteners and let droop. I then snugged fasteners then lifted axle with jack and got same result. I think springs are bad.
 
Well this is interesting because I have the same springs and ordered them around the same time you did. I have yet to install them, this might usher me along to find out if they are good or not. Or if you need some relaxed dimensions I can measure mine.
 
Well this is interesting because I have the same springs and ordered them around the same time you did. I have yet to install them, this might usher me along to find out if they are good or not. Or if you need some relaxed dimensions I can measure mine.
 
I just spoke with my local Chrysler dealer who are happily replacing the springs, chalking it up to defective parts. This time we are going with p4529414 springs with 0 arch, stock ride height. The spring arch shape was causing my pinion to point upward a lot. I will keep you all posted.
 
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