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Low Rear Spring Height

Stretch

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I recently replaced a broken rear spring on my BJ7 with a new spring from Moss. I was surprised to find that the new spring compressed about 0.75 inch more than the old spring on the other side. Having minimal ground clearance already I think the softer spring played a big part in scraping bottom several times on the trip to Watkins Glen this past weekend. Does anyone know who supplies Moss with their springs and/or a better supplier?
 
Hi Stretch I think all the springs come out of the same bin. However, springs should be replaced in pairs and their travel adjusted after installation.--Fwiw---Keoke
 
I bought Moss springs a couple of years ago and was disappointed that the car actually sat lower with the new springs. I ended up taking them to a spring shop. They told me there was no "SET" between the leaves. Each leaf actually laid flat against the next one when the spring was unbolted. Apparently, there should be some space (arch) between each leaf. Anyway, he rearced the leaves and it raised the car back up, although not quite as high as I wished
 
Hi Skip,
There is a limit to how high the ride height can be set.

These cars with their underslung frames are a compromise on rear wheel travel. If the ride height is set too high, the axle will be continually topping out (hitting the frame under it) which causes as much or more handling/ride problem as riding too low & bottoming out. Experimenting with shock compression/rebound settings can optimize the setup. I speced heavier rebound damping on the "World Wide Auto" rebuilt shocks which helps control the limited rebound travel.

I think you want around 1/3 rebound travel & 2/3 compression travel as a decent compromise. The large rubber compression bumper allows for some extra compression travel, but the very thin rebound bumper doesn't give much extra rebound travel. Late BJ8's have a little more travel to work with but are still a compromise.

My Moss springs have about three years on them & have stopped settling at about 1/2" lower than when originally installed. I did lower the front about one inch with 1/2" spring pan spacers to get the car level front to back. A ride height of around 27" measured from bottom of wheel arch to ground on the wheel center line is usually thought to be optimum. 28" on the late BJ8's I believe.

As an aside, I find that the Moss springs,(DAUR) have an extra wrap around on the spring eyes that does not fit tightly around the main spring eyes. These loose pieces constantly rattle as the car goes over light bumps. The so called clamps just don't hold them tightly. I "solved" the problem by driving aluminum wedges between the offending parts but the wedges tend to work out & require continual tightening. Has anyone else had the problem & what was the solution?
D
 
Some good thoughts! I'm going to jack the car under the low side U bolts just to check the frame for twist but it looks pretty straight. I'll take the old spring apart and check relative arcs. Might talk to a spring shop. By the way another guy with a BJ7 had the same problem with new springs.
 
Hi Stretch/ Shorn, this problem with the springs is just the opposite of what we were experiencing a few years ago. The after market springs would set the ride height way too high. Consequently, they had to be tuned by shifting new and old spring leaves around or removing new leaves waiting until the springs settled 1/2" then replacing the removed one. If you have access to a shop that can rearch springs it is best to have the original ones redone.--Fwiw--Keoke
 
Yeah, I was one of them "High Sprung" guys that you helped. Guess the pendulum has swung the other way now.
 
With the new Moss rear springs, my ride height from ground to high point on the wheel arch on the fender was only 25 1/2 inches, way too low. Rearching the new springs brought the height to about 26 1/4. Ultimately, I ended up rearching the old springs which raised the car to about 26 3/4, very close to correct level. the new Moss springs now occupy the corner of my garage. Moss made good on the springs, by the way. They are excellent in dealing with customer satisfaction. My BJ8 is a phase 1, so it has the lower height of the big healeys.
Keoke--it seems that the problem of new springs causing the height to be too high has been over corrected.
 
Shorn,
Re-arching springs will take care of the problem for a while, but probably not a long time fix. When a spring is made, it is tempered & drawn to correct hardness, after it is formed. After a bit of initial sag to final set it should hold for a long time.

When a spring is cold re-arched it is in essence just bent to a new contour. If it is not re-heat treated, it will eventually go back to it's old contour or less.

Old time spring shops had heat treating equipment to do this sort of thing. I haven't seen many modern spring shops that have heat treating equipment. I hope you found one!

As Keoke said, juggling various spring leaves to the desired result is likely to give longer life than just cold bending the springs.

Maybe you are not after many years of additional spring life, if so, it doesn't matter.
D
 
Dave,
You are absolutely correct. My rearched original springs have dropped a bit over the last couple of years. And no the spring shop did not reheat them.
skip
 
Re: Low Rear Spring Height--fixing the rattle

Regarding the rattle of the end loop on the Daur springs:

I was able to permanently fix the rattle by making shims from 1" wide, 1/8" thick aluminum and inserting them between the top of the clamp and top of the spring.

1" is enough wider than the clamp that one can bend a small lip up on either side which will keep the shim from falling out. The clamp is removed, shim inserted and clamp replaced.

Interestingly the rivetted clamps have enough of a gap in them to allow you to insert one of the old spring leaves in as an additional leaf.

I also used high pressure teflon tape as a liner between each leaf--this is available from Annapolis Performance Sailing.
 
Re: Low Rear Spring Height--fixing the rattle

Just an update going back to my original post.... When I disassembled the new spring I found that the inter-leaves had up to one inch less arch than the original leaves. They were also poorly formed. The main leaf arch matched the original main leaf pretty well. I compressed old to new leaves back to back, and the old leaves won in all cases. I made up a spring using the new main leaf and old other leaves and got a restored and pretty level ride height.
 
Re: Low Rear Spring Height--fixing the rattle

Stretch said:
Just an update going back to my original post.... When I disassembled the new spring I found that the inter-leaves had up to one inch less arch than the original leaves. They were also poorly formed. The main leaf arch matched the original main leaf pretty well. I compressed old to new leaves back to back, and the old leaves won in all cases. I made up a spring using the new main leaf and old other leaves and got a restored and pretty level ride height.
Good job!

Sometimes you have to take the best of what you have, and the best of what you can get to really get what you need.

There's little doubt that the currently available reproduction parts for our cars pales in comparison with the originals. I guess we're just lucky for what we can get.
 
Re: Low Rear Spring Height--fixing the rattle

Stretch - Way to go. It's a shame that we can't get correct springs out of the box, but more often than not, your method is the best solution, as Keoke said earlier.
D

Steve - I used the aluminum shims the first time but didn't bend then & they keep working out of place. I'll try your suggestion.
D
 
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