Oh what fun this job is! As many already have experienced this is not a job for the impatient. It will also get you real intimate with your car!

If you have not done this or the PPO's have not touched the Torsion assembly I would highly advise you do it. The rear bushings, particularly the T bar carrier bushings are most likely shot! There was not one bushing on the rear in good condition for my 87! Replacing them is a major improvement but difficult to do for the DIY'er unless you have a shop with air grinders, chisels etc. Also plan on the car being down for a few days depending on your skills.

Well after much "blood letting" I have come up with a way to reindex bars without boring a hole in the body panel. Unfortunately the entire rear suspension must come off once to use the new way to reindex. But after it only takes a couple of minutes to index.

What some have done is bore a hole and cut the Torsion tube cap off and pull the bars out the side of the body. I did not wish to bore a hole so I drilled and tapped the T bar with a 3/8 tap and use that to get a hold of the T bar to pull out. Cut the cap off and made a new cap that is split on the side with a bolt and nut welded to each side of the split creating a clamp style cap. Loosen the cap and remove it to access the bars. Now for the easy part, place a jack under the trailing arm at the shock mount (remove the bottom shock bolt) and raise the jack just where it touches the arm. Loosen all 4 Torsion tube carrier cap (spring plate). Now you can take the tension off the bar and reindex it by attaching the 3/8 bolt on the end and pull it out just enough to free the plate. Jack the arm up or down depending on if you are lowering or raising ride height the distance needed to change. If too high raise the spring plate push the T bar back in and tighten all bolts and release jack the arm will stay where you set it.

This method is huge when reindexing as you must remove all the suspension to re set the bars if not removing the T bar caps and or boring holes for access. As you may know in order to get the ride height and corner balance correct this removing the Torsion bars must be done a number of times 3 or more, less if really blessed!

Now you can change the ride height in minutes instead of days! (generally speaking)....Sorry no pics as it would not show much other than blood splatter! lol....but will try to get a pic of the caps I fabbed for your visual enjoyment......Email or post for specifics!! Regards! Dal

 

This is certainly useful info for the future (one day I want to install thicker torsion bars).
I didn't fully understand how these new caps work, so yeah, pictures would help.
Good job!

 

Sounds good, but I have method to install torsion bars that will take only one time to do it right.

The one time torsion bar reindex procedure

I have done two torsion bars first from 23.5 to 28 and the 28 to 30 mm. I got it right the first time on both using the procedure and the excel spread sheet. Others have used it with success too.


I really fail to understand why people cannot get thise done right the first time. I have had this procedure for years and those that try it and take carefull measurements prove that it works. Then again other still FEAR the BARS and don't want to touch them or need do it 2-3 times to get the ride height correct. It is really not that hard!

 

M758-
Thanks for that link (from my 25.5mm indexing post yesterday). I haven't looked at their formulas to figure out how they take into account the different bar diameters, but it looks solid.

-nick

 

M758.....OH MAN that is the method that I was going to use but lost the info on it! And you had to post it after the fact!! LOL! Yes that is a good way to do the job if only replacing bars but in my case the entire system had to come apart to install all new bushings. Kind of hard to air chisel the bushings while the rear suspension is whole. All done now except for the corner balancing, hoping it is on the scales right now! Thanks! Dal

 

All I did was take a piece of aluminum tubing with an ID just snug enough to fit over the old torsion bar end cap cut it to a 1 1/2 " length. Welded a cap over the bore in the aluminum tube and cut a slot running the length of the cap. Welded one bolt on one side of the slot and welded a nut on the other side. When tightened the slot moves together and clamps over the T bar cap tube. Dal

 

I just realized this was my first how to posting! I seldom offer info on how to fix something for the fear of screwing someones car up if the advise was wrong or the wrench did not do it or understand it correctly. Sure don't want someone coming back to me and blaming me for their car being messed up! Dal

 

Torsion bar stiffess goes by 4th power of the diameter. There is a texted book formula for the stiffness of bars in torsion. In my formulas I basicly meaure the stiffness of the bar that is in the car. That is where you take car to ground measures. Then since the change in diameter changes stiffness to the 4 power. Viola... I can figure the new stiffness assuming everything else is constant. Not 100% accurate, but good enough since you can use the spring plate for small minor adjustments. It is however much better than stuffing in a new bar and hoping it right.

 

Thanks everyone for posting. I'll be doing a bar upgrade this fall and have bookmarked this topic for use then.

 

Me too, I'll be re-indexing the stock bars as soon as the paint is done on the car.

 

what sort of bushings to buy..... what do you recommend? kokelen?

 

Wow, this sounds like so much fun I think I'll reindex my bars every weekend for the rest of the summer!

 

Sweet thanks for the info guys...

DAmian

 

Sorry to bring back the ancient thread - I am "upgrading" the torsion bars on a friend's car and this post has a dead link to az.pca.org for a procedure to perform the "One Try 944 Torsion Bar Index"

Does anyone still have this writeup somewhere? It would be helpful! Sway-A-Way sent some info on setting the right angle but I'm not sure I trust it...

 

I tried searching 'one step...' but didn't have any luck. I would, however, use Clark's Garage for help on this subject (and everything else tech for our cars).