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-   -   “Loading” Front Suspension for Re-Install (https://rennlist.com/forums/928-forum/1404747-iloadingn-front-suspension-for-re-install.html)

streetsnake 03-24-2024 10:37 PM

“Loading” Front Suspension for Re-Install
 
So in preparation for my front end reinstall on the ‘79, and save poor @Rob Edwards from all my questions, I thought I’d put out a message for creative ideas. I don’t have a rack but I do have 12” wheel cribs. Any ideas how to get the shark’s suspension under load to torque the UCAs & LCAs. Is it then possible to torque everything else at the same time…steering knuckle, ball joints, etc. I have one idea but I figure you all know way better than I do. :)

Tony 03-25-2024 12:39 AM

you don't really load per say, but rather let it finds its own neutral point under it own weight at its set ride height.
IIRC there are only 4 bolts (2 each side) that you don't fully torque down, the aft lower control arm bolts. (don't quote me on that) I left mine "loose" and drove for a while over a few local bumps etc and then reached under the car with out lifting it and torqued them spec. 87S4

depami 03-25-2024 07:28 AM

What do your wheel cribs look like? Maybe you could put a bar through your cribs and attach ratchet straps or turn buckles to some solid frame member and pull down as per work shop manual.

buccicone 03-25-2024 08:24 AM


Originally Posted by Tony (Post 19350789)
you don't really load per say, but rather let it finds its own neutral point under it own weight at its set ride height.
IIRC there are only 4 bolts (2 each side) that you don't fully torque down, the aft lower control arm bolts. (don't quote me on that) I left mine "loose" and drove for a while over a few local bumps etc and then reached under the car with out lifting it and torqued them spec. 87S4


This what we do. With new bushings, I could not get it to settle without loosening the 4 bolts of the lower control arms. Of course don’t drive like a maniac while they are loose.



hacker-pschorr 03-25-2024 09:57 AM


Originally Posted by buccicone (Post 19351009)
This what we do. With new bushings, I could not get it to settle without loosening the 4 bolts of the lower control arms. Of course don’t drive like a maniac while they are loose.

Be careful guys. I know someone that did the same years ago (Jeez, like 20 now). Never went faster than 5-10mph tapping the brakes to get the nose to settle. Maybe he drove a bit too much, I dunno, but the lateral force on the bolt had enough wiggle room to damage the threads in the frame. We were able to drill / tap it.

If I didn't have a lift, and since it's going to need an alignment anyway, I would just have it flatbed to a shop that I've already qualified to finish the job. IMO some things should just be done with the proper tools and procedures.

Mrmerlin 03-25-2024 12:44 PM

NOTE the rear clamp bolts should not be more that 2 turns out from tight.
I like to use 1 1/4 loose.
this will let the clamps have room for the bushings to settle into their loaded position.

NOTE since the cross member has alignment collars built into it,
the clamps cant slide past these collars unless the bolts have been left too loose.
Nor can the bolts be side loaded since the clamp plate movement is restricted.

Then once your back from around the block, park the car on a flat surface .
I slide on a piece of cardboard to use the torque wrench to final tighten the rear clamp bolts to 86 Ft/lbs.

worf928 03-25-2024 03:36 PM

Just about every fastener that bolts through a bushing should be torqued-to-spec at nominal ride height:
- rear bolts, front lower control arm
- pivot bolts, front upper control arm
- front coil-over bottom bolts
- rear dog bones
- rear drop links
- etc.

You can get “pretty close” with wheel stands on grease plates for the ones you can’t do “wheels on” on a 4-post after factory pull-down.

If you want details you know where to find me.

Rob Edwards 03-25-2024 03:58 PM

I can't tell you how many times I have driven the 15 miles to Greg's for an alignment with the rear bolts of the lower control arm, the lower shock bolts, and the upper control arm nuts loose. I try to keep it under 65. Haven't died yet. (Knocks on MDF desk).


streetsnake 03-25-2024 06:14 PM


Originally Posted by depami (Post 19350976)
What do your wheel cribs look like? Maybe you could put a bar through your cribs and attach ratchet straps or turn buckles to some solid frame member and pull down as per work shop manual.

Here is what I have. Maybe I can drill holes into them and slide a black pipe all the way through?? I haven’t consulted the WSM yet, as I first wanted to figure this out. I imagine red-neck engineering is not found in the appendix. :)
https://www.raceramps.com/cribs/wheel/p/rr-wc-12-sc/

depami 03-25-2024 11:44 PM

https://cimg5.ibsrv.net/gimg/rennlis...f3bd416c10.jpg

Brent A. 03-26-2024 12:00 PM


Originally Posted by streetsnake (Post 19352244)
Here is what I have. Maybe I can drill holes into them and slide a black pipe all the way through?? I haven’t consulted the WSM yet, as I first wanted to figure this out. I imagine red-neck engineering is not found in the appendix. :)
https://www.raceramps.com/cribs/wheel/p/rr-wc-12-sc/

I would not attempt that with the RaceRamp product. The material that they make those out of pretty sturdy but I have seen some of their products, mostly the trailer ramps, begin to loose their firmness after repeated uses. I would concerned about it withstanding the forces created in using the pull down procedure.



Mrmerlin 03-26-2024 12:08 PM

NOTE with the pull down procedure it will be beneficial for the wheels to move sideways,
like keeping the wheels on moveable plates.
NOTE most owners wont have a rack that can be driven onto then the wheels driven onto moveable plates .
I suggest to put the suspension together ,
leave the sway bar links snug, the rear LCA clamps 1 1/2 turns loose, the upper control arm bolts snug ,'
drive the car around the block park it on a level spot.
Then torque the LCA rear bolts with the car on the ground turn the wheels to full lock and tighten the upper control arms,
drive the car 50 miles to settle the suspension .
NOTE you may have to reset the ride height prior to going for the 50 mile drive,
if so perform this after atleast 10 miles..
After the drive,
drive the car onto your alignment rack and final tighten the lower shock bolts and the sway bar links
recheck the rear LCA bolts and the front LCA bolts and the ball joint nuts.

NOTE this procedure results the having the suspension settled and the most accurate alignment performed.

NOTE the suspension will continue to settle into its harmony point ,
this point should be reached at about 500 miles,
However the initial 50 miles gets it pretty close to perfect.


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