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Packard Crew-

I have been doing A TON of reading regarding our beloved torsion bar suspension and what can and can't be done to modify it. As with a few other folks that I have seen on here and various boards, I want to lower my Packard just a bit as I try and customize it. I don't want to destroy the handling, just want to settle her down a bit. With that said, I have a decent understanding, I think, of how the suspension functions. I have found a place that makes the adjustable links which would probably get me the desired 1-2" drop all around I'm looking for. However, for the other folks that want to go lower, I have considered today's modern torsion bars suspensions in trucks and how various systems use different "keys" or "reindexing" the torsion bars to get lift or lowering. Would it be possible to "rekey/ reindex" the main torsion bars? This would perserve the function of the suspension, but by doing this the whole car would essentially drop or raise accordingly, right? I may have missed something in my theory, which is why I'm asking here, what do you think?

CDR D

I'm not an engineer but my instinct says they could not be reindexed -- at least not without a huge cash outlay and access to a facility with engineering talent and capable of heavy forging and fabrication.

The bars were made, pre-stressed, heat treated and the works thrown at them to give a specific amount of lift at a given weight and not break or lose strength when at maximum twist. The original 55 issue bars were found to be less than satisfactory on some heavily optioned cars so a limited quantity of new bars were made with an additional twist to provide more lift.

The arms are heavy forgings. IMO, that would be the only logical place to do any index changes. Whether you could find a place to make something and afford to get it made and treated would be the question. Broaching the hex shaped hole would be an obstacle so cutting and welding would probably be the only hope of modifying an existing arm. I know I would be reluctant to trust a cut and re-welded arm at full load.

The rear stirrups are a welded piece. If any extra lowering were to be accomplished other than shortening the front links, possibly an extra bit could be welded in the middle of the stirrups. That would allow for a bit of a drop but no idea how much would be possible to add without causing suspension issues or for them to become too low and turn into a road obstacle catching device.

One other obstacle to lowering via the suspension is the A arms would be off center with respect to the bumpers as would the rear components to their bumpers. The least little bump would probably have one end or the other smashing into the bumper and then the frame when the rubber is toast.

If you haven't already looked it over, there is an SAE publication on site detailing the design and theory behind the making and working of the system.https://www.packardinfo.com/xoops/html/downloads/SAE_Torsion.pdf

As HH56 says, I'd really hesitate to alter the bars or the load arms. If your car currently has 4-groove pins in the front and you install 1-groove (or their equivalent length) you should lower the car just a bit over 1 inch. I'll admit I'm timid about major alterations, changing front pins would be as far as I would go. If you really want to significantly lower a V8 Packard further than that, I'd start with one with the conventional suspension.

As usual, I agree with the posts of HH56 and O_D. Let me add a couple other thoughts.

I was probably the original innovator of the adjustable front links; if not the original then one of the first.

http://1956packardpanther.com/Panther/adjLinks.html

My motivation was to restore my 1955 Patrician to it's original ride height (both sides had sagged) and to correct the driver side which had sagged about 1IN more than the pass side. In this, the adjustable links were completely successful.

That having been said, if I wanted to lower the static ride height of my Panther (which I might do) and not screw up the T-L performace including constantly riding on the A-arm bumpers, then I would do it "old school." Take off the front king pin assembly (Gp 15.501) and modify it to raise the wheel with respect to the front A-arm assemblies, i.e., a "dropped axle." You could do the same "old school" thing with the rear suspension, i.e., put "lowering blocks" between the axle housing and the rear trailing arms. Both of these lower the respective ends of the car without altering the T-L at all.

On edit: one more "old school" technique I forgot to mention is "channeling". This entails modifying the floor of the body and lowering the frame outriggers and who knows what else. This will lower the body over the frame so the car appears lower, but the T-L is unaffected.

Craig

Sorry that I cannot offer any advice on reindexing the TL suspension, but I have a shameless plug about a DVD that Motor City Packards sells - it is interview with William (Bill) D. Allison, the inventor of the TL suspension.

The DVD is copied from a VHS tape that was produced in 1989 by MCP member Russ Cramer when he interviewed Bill along with Joel Ray (packards1). The best part is that Bill voices over a series of movies he took in the mid-1950s when they were testing a 1955 Packard Patrician vs. a 1954 Cadillac and 1954 Lincoln on the streets of Detroit. You also get quick views of the Packard Plant and Proving Grounds when they were still in operation.

It is a nifty piece of Packard history that we sell for $17 and that includes shipping. You can PM me or use PayPal PackardClubMI@aol.com We have 10 copies in inventory ready for holiday shipping.

Thanks,

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And let me add that I have the DVD and it is a very nice addition to anyone's library who is interested in TL.

There is one more TL video I would like to find a really good copy of. In the early 80's at the PAC meet in Berkley, CA there was a movie shown of a driving comparison of Packard, Cadillac and Lincoln. All cars were covered and took that RR crossing at speed that is shown thruout the DVD. The DVD item may even be a portion of that same test & movie but at any rate, the stand alone movie seemed longer and funnier. For those that haven't seen it, the test results were quite amusing. Worth a show to any of your friends promoting brand X superiority.

What I take away from RogerDetroit and HH56's previous posts is:

DON'T SCREW AROUND WITH THE ORIGINAL T-L SUSPENSION. Except for adjustable front links which perform essentially the same function as the fixed different length links from the factory, of course.

Craig

Packard Crew-

I apologize for misleading you all to think I would consider messing with the torsion bars themselves. I agree that's a huge error and would never pan out. What I'm suggesting is replacing the front load arm with a different unit. In modern truck suspension the "front load arm" is referred to as a "key." You can purchase a different key that would ultimately change how much preload is on the torsion bars and effectively raise or lower the vehicle. The difference in the key is minute, but I agree now that effecting the preload will affect the ride, good point.

With that in mind, I like Craig's old school approach of modifying the front spindles and placing lowering blocks in the rear. I'm looking at the adjustable links and this approach as my leading options. Channeling is WAY too much work for what I want, a cool daily driver.

I've read on other sites that it is difficult to "bag" or install an air suspension on these cars. Why could you not just remove the torsion bars altogether and place air bags where the front shocks are and air bags where the rear shocks are? I understand there's some custom mounts to be made. And I only ask the question to educate myself on the limitations of customizing this platform and not trying to disregard anyone's opinion.

CDR Dan

The only thing you could change in front would be the links or "pins". The front load arm itself has the hex hole to receive the bar. There is not enough range to relocate the load arm one hex off to give a different amount of twist. I am thinking what Packard called links has the same function of the piece you are calling keys since both affect the twist of the bar.

The rear is essentially the same configuration except with a stirrup instead of a link. Changing the length of the stirrup by making it longer would in effect be doing the same as changing the length of the pin and making that shorter. Either would result in slightly less twist so car would be lower.

Cadillac tried air bags for years. How many people are out there praising them today? My brother had one that made you sea sick waiting for the rudder to bite.

You have a car with a smooth, gentle ride that is the absolute king or railroad tracks, and which doesn't wallow like an old sow on turns.

Are you related to the guy who spent his life "improving" the works of Mozart?

What are you hoping to gain, besides lowering the car a trifle? You need all the clearance you can get. I don't want to be there when you change or rotate tires....

Coffee! Bring this individual black coffee. Keep it coming.