Hotchkis leaf springs sagg brand-new

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Ride height is easily addressed in several different ways. The main issue is those springs are too long. If you want that (type) spring I'd ask Hotchkis if they can exchange them for a set about an inch or 1.5 inches shorter.
 
The rear hangers are stock, the shackles should be...all the front is from Hotchkis. Here is jrlegacy23's thread of his build with stock rear shackles (note spring has been relocated though). He removed Hotchkis' front mount to remedy this issue. This seems to be an issue on 111" wheelbase cars and not 108" (bc of weight distribution as ive gathered). If Hotchkis engineered this system correctly one shouldnt have to remove their front hanger (which they claim corrects the geometry) and put the stock back on to make it work;it was sold as a system.

http://www.forabodiesonly.com/mopar/showthread.php?t=179035

340-4spd: All dimensions i gave to Hotchkis check out, the springs dimensions are correct, it has to be the rate that is the issue; refer to my post #7 to GMachineDartGT's quote from his thread of the same issue...
 
This is the part I keyed on:
dustbull said:
For the record, I did call Hotchkiss and ask for designed install heights, and they had none."
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I belive Hotchkiss assumes people using these springs are doing major fab work building a car anyway and will not be concerned with what they probably deem a minor fitment issue for drilling new holes like jrlegacy23 did. A new hole in a more favorable location there would solve your problem and potentially add some lift depending where you put it.
 
The reason I think you need stock rear shackles isn't because of length. Notice Autox pic of the reliefs in the shackle that make them narrow in the middle to clear the frame rail. The shackles are as far angled as they are gonna get when sitting at static ride height. I think if you used stock front hanger and shackles you would be golden. Other than spring wrap.
 
340-4spd:
It would if i had relocated my springs like he did, I however feel Hotchkis' targeting market is the bolt-on mechanic...I see myself as in between these two extremes, and had relied on Hotchkis' engineers to design something that has proper suspension geometries once installed. When its application specific like '67-76 A-body leaf springs' i assume most of the research has already been done. But as has been proven time and time again-never ***-u-me anything

72BBSwinger:
I noticed the relief on the stock shackles, so lets assume that will give me some clearance at static ride height. The stock hanger will move the height up an inch, maybe give me more clearance, but i can almost guarantee that any slight bump i hit on the road and the shackles will be slapping the subframe hard.
 
dustbull said:
...but i can almost guarantee that any slight bump i hit on the road and the shackles will be slapping the subframe hard.
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If they sit at 0 degree arch like 72BBSwinger said, they can move no direction but forward with flex.
 
340-4spd said:
If they sit at 0 degree arch like 72BBSwinger said, they can move no direction but forward with flex.
Click to expand...

That is a good point i hadnt thought about...

Ill have to do some thinking and some research, ill be working on the car friday, so i have a few days to think
 
I would change the front hanger to stock and do the factory shackles or notch those if it still contacts take one of the shorter leafs from the /6 spring packs and add it into the hotchkis pack.

Or leave it how it is and add a shorter leaf or 2 from the /6 springs and get an adjustable pinion snubber.
 
dustbull said:
340-4spd:
It would if i had relocated my springs like he did, I however feel Hotchkis' targeting market is the bolt-on mechanic...I see myself as in between these two extremes, and had relied on Hotchkis' engineers to design something that has proper suspension geometries once installed. When its application specific like '67-76 A-body leaf springs' i assume most of the research has already been done. But as has been proven time and time again-never ***-u-me anything
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You don't have a bolt on car. You've fabricated yourself a lot of modifications to it allready.
  • You are running a modified/cut down? Dana back there. What is your pinion angle on that Dana? Where the perched welded on with the right pinion angle.
  • You have aftermarket rear shackles. Are they stock height?
  • You are running a T56 trans with a homemade trans mount. The engine and trans may be angled up or down from stock position
  • You have a solid motor mount. The engine and trans may be angled up or down from stock position


72BBSwinger:
I noticed the relief on the stock shackles, so lets assume that will give me some clearance at static ride height. The stock hanger will move the height up an inch, maybe give me more clearance, but i can almost guarantee that any slight bump i hit on the road and the shackles will be slapping the subframe hard.
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The rear shackles are perferred to angle back a little. No matter what leaf springs you have on there. It's ok to have them angled foward. but angled back is perferred. I think that is stated in the Super Stock spring instructions. No sure. But it is stated in the Mopar Peformance Chassis Manual.
 
autoxcuda said:
The rear shackles are perferred to angle back a little. No matter what leaf springs you have on there. It's ok to have them angled foward. but angled back is perferred. I think that is stated in the Super Stock spring instructions. No sure. But it is stated in the Mopar Peformance Chassis Manual.
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The shackle angle has marked effect of leaf spring tuning characteristics. The "preferred" angle of the shackle depends on what you are trying to accomplish with the rear suspension:

attachment.php


The way they are running these shackles from what I have seen posted in this and the related thread is giving the max or near max spring rate. But with the Hotchkiss springs running zero arch, I believe conventional wisdom on this setup might be out the window.
 
autoxcuda said:
  • You are running a modified/cut down? Dana back there. What is your pinion angle on that Dana? Where the perched welded on with the right pinion angle.
  • You have aftermarket rear shackles. Are they stock height?
  • You are running a T56 trans with a homemade trans mount. The engine and trans may be angled up or down from stock position
  • You have a solid motor mount. The engine and trans may be angled up or down from stock position
Click to expand...

I had measured the pinion angle a while ago, in the initial T56 swap, but dont recall what it is...but we did order the diff from Strange, it is stock a-body width, perches are welded at stock width as well..so it should presumably be at stock pinion angle.

Shackles were what the car had when we bought it, never thought anything of them...comparing pics now it looks like the shackles may be 1" shorter

I had measured engine/trans angle before and after the T56 swap, i made sure it remained the same (this was also when i put the solid motor mount in).

Thanks everyone for the thoughts and comments!
 
I wonder if Hotchkis knows A-bodies and E-bodies do not share the same front hanger dimensions (other than the body bolt pattern)?

Looks like the hole in the front spring hanger is too high, and your rear shackles are too wide and too short.

If you ordered the rearend directly from Strange, the spring perch to pinion angle will not be correct for a "stock" A-body. Unless you specified otherwise, Strange installs the default perch/pinion angle at 7 degrees positive, which is correct for an E-body but 2 degrees farther up when installed in an A-body.

To further compound the problem, because you installed a T-56 transmission, you can not confirm your pinion angle or driveline angle, until you measure every thing correctly.

You can install stock A-body front hangers and shackles and reset the pinion angle based on the transmission centerline NOT to the ground, NOR to the driveshaft.

In other words, AFTER you correct the hangers and shackles, when the vehicle is resting on its suspension, make the pinion parallel to the transmission as a base-line, then roll the pinion downward 2 degrees and reweld or shim your perches. The result is a true 2 degree negative pinion angle.

This should improve the vehicle's stance and driveshaft clearance.
 
DoctorDiff said:
If you ordered the rearend directly from Strange, the spring perch to pinion angle will not be correct for a "stock" A-body. Unless you specified otherwise, Strange installs the default perch/pinion angle at 7 degrees positive, which is correct for an E-body but 2 degrees farther up when installed in an A-body.

To further compound the problem, because you installed a T-56 transmission, you can not confirm your pinion angle or driveline angle, until you measure every thing correctly.

You can install stock A-body front hangers and shackles and reset the pinion angle based on the transmission centerline NOT to the ground, NOR to the driveshaft.

In other words, AFTER you correct the hangers and shackles, when the vehicle is resting on its suspension, make the pinion parallel to the transmission as a base-line, then roll the pinion downward 2 degrees and reweld or shim your perches. The result is a true 2 degree negative pinion angle.
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Thanks DoctorDiff, VERY informative! I had told strange the application of the diff along with the spring perch width, but i did not specify a pinion angle, so it probably is at the E bodys spec...

I had used an angle finder on the output of the transmission (both a-833 before and t56 after) so i feel that end should be as though it is stock. Assuming that the shackles are an issue and make an improvement, couldnt i find the pinion angle as-is and adjust it to be at 5 deg without putting stock hangers on?

Ive been swamped with school and work, but i just ordered a set of "stock" mopar shackles to be next day aired to me for the weekend. On the Hotchkis side, they have been very helpful and have made it a priority now, so we'll see what this weekend holds.
 
The 5 degree thing is not what you want. The driveshaft angle is irrelevant its the pinion angle in relation to the transmission tailshaft that needs set 2 degrees down from parrallel.
 
72BBSwinger said:
The 5 degree thing is not what you want. The driveshaft angle is irrelevant its the pinion angle in relation to the transmission tailshaft that needs set 2 degrees down from parrallel.
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Yes, ive found a few good diagrams...make the trans and diff parallel
 
dustbull said:
Yes, ive found a few good diagrams...make the trans and diff parallel
Click to expand...
No 2 degrees "down" from parallel on the pinion. Minimum. Especially with those springs, unless you have some wrap control. I'd guess you'll probably want 3 or 4 degrees down if it's making much power.
 
Actually in my experience I would recommend with new springs to start at 4-5 down. I set mine at 3 when I put it together and after about 500 miles it needed a 2 degree shim. That little tid bit I almost forgot about.
 
This is where i get lost though...If the transmission is at a 'negative' angle, then the differential shouldnt be (to prevent u-joint binding) correct?
 
If the trans is 3 degrees down then you want the pinion 1 degree up. And this in relation to the ground, like with your rockers bubble level. So if I was you and my trans was like above I would probably set the pinion 1-2 down in that case with the hotchkis springs. Ideally you want the trans and pinion parrallel under full power.
 
Well i have to admit that the shackle gave it more clearance than i thought it would. The only issue is that the idiot Summit tech told me i only needed to order one instead of the two i had ready to order in my cart. So i will be making my own shackle for the other side tomorrow.

The other issue is that the rear still sits so low, below is a picture of the pinion snubber ~1" clearance to stop and the u-joint ~2" clearance from floor (note where it had rubbed previously). Is the Dana 60 taller than an 8 3/4" by the pinion/input, ive never really looked. Im going to bash the tunnel in with a 2x4, maybe cut it up if need be.

DSC01619.jpg

DSC01617.jpg

DSC01615-1.jpg
 
The yoke on a Dana is closer to the front of the car which accounts for that issue. My snubber is about 1.5" from the floor but it is the soft rubber type. Did you put your stock front hangers in?
 
Can't get an idea of the pinion angle (relative to the trans output), but the rear joint looks like a straight shot - not good. I'd be looking at some 2 degree shims to rotate the pinion down before I started doing anything radical with the floor.
 
I just changed the rear shackles, nothing else...still considering if i want to change the front hangers out or not (need to sand blast/ paint them).

the picture is decieving on the pinion angle, its pretty decent...havnt put an angle finder on it yet, but i will be. I put a larger dia. bump stop on the pinion snubber and bashed the floor in by the ujoint. After a few hard acceleration tests it doesnt rub anymore at least.
 
Im just popping in again to voice my displeasure with these springs-they are a joke, I hope this makes some people question quality (even from a reputable company). I spoke with one of the techs at Hotchkis months ago, great customer service, the measurements all checked out on these springs, BUT they refused to consider that the metallurgy was incorrect with these springs.

The pictures below are after 13,000 miles. All stock hangers are installed because the Hotchkis supplied front mounts made the car sit even lower. It may not be as clear as in person, but these springs definatly appear to be bowing upwards. IF these springs are fine, I don't want to see a set that are faulty. Im afraid to think of what these things look like during hard acceleration...



Because of these springs, ill be investing more of my time and money into pulling these things off the car, throwing them into the garbage where I think they belong, and designing a 4 link like I should have in the first place...Ill also be placing an order with HELLWIG for the sway bars.
 
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