Torsion bars vs coil springs

[Roadman]

            Is there an advantage ie. weight reduction, cost. to using bars rather than springs? I think only Chrysler used them in there cars.  Personally I don't like the design. When I had a 68 Satelite race car in the 70s we couldn't pull it with a tow bar. It wouldn't follow on a turn.   

[RUNCHARGER]

A coil spring is really just a Torsion bar that is wound. The difference is the coil spring becomes unsprung weight while the torsion bar doesn't. Hence the Torsion bar design is actually superior. Another benefit of the traditional Chrysler Torsion bar setup is that it slightly shifts the CG towards the back of the car as compared to coil springs which have all of their mass centered at the front wheel center. Then there is the fact that ride height is adjustable with a Torsion bar setup whereas the coil springs must be cut or changed to adjust ride height in a coil setup. I'll take Torsion bars any day of the week over coils.

[Chryco Psycho]

approx 3 things , the torsion bar is just an unbent spring , but it sits lower in the chassis & closer to the middle of the car which is far better for handling , it is easily adustable as well & it is safe to install& remove , the last point is the chassis was never designed for a coil spring or coil over shock design as it places the load on the inner fender not the trans crossmember , so now you need a shock brace over the engine which I realy hate

[cataclysm80]

If the 68 Satellite had stock torsion bars, they probably weren't anywhere near stiff enough for cornering a road race car, ESPECIALLY if a larger heavier "race engine" had been installed into the car.

springs (regardless of whether they're torsion or coil) need to be chosen based on the weight & forces that they're expected to handle.
measured as Spring Rate

A torsion bar has a 1:1 motion ratio, while a coil spring does not.  To get an equal wheel rate, I'd think the coil spring would be heavier, but I haven't weighed them.
The weight of a coil spring is entirely on the front end, while the weight of a torsion bar is mostly behind the front end, so I suppose that could help a little with front to rear weight balance of the car.  (sort of like moving your battery to the trunk would do)

[Chryco Psycho]

Looks like we all posted the same thing at the same time , there were no replies when I started typing my response !!
I doubt there would be significant weight difference between a T bar & coil as it will take the same thickness of metal to create the spring rate & similar distance to allow for the travel 

[cataclysm80]

You mentioned cost.
I'm not sure how the manufacturing cost would compare, but if you have a Mopar that's already designed for torsion bars, then installing a good torsion bar setup will be MUCH cheaper than buying a kit to convert the car to coils.

[Roadman]

   Thanks guys. I still tend to think they were used for lower cost. I mean the average guy buying a Chrysler didn't care about ride height adjustabilty, weight transfer, etc. And they didn't care about handling. 99 % bought a car to get to work, get the groceries, etc.  Now the muscle car guys did, but that was a small percentage of buyers. Food for thought.   

[Chryco Psycho]

Chrysler engineers were at the top of the game , the customer may not have appreciated the difference but the engineers made sure it was the best .
Once Mopar quit using T bars Chev trucks & other started using them a lot , Vw bugs used them for decades

[Roadman]

 Or not      Look at advantages/disadvantages.   https://en.wikipedia.org/wiki/Torsion_bar_suspension

[Chryco Psycho]

Variable spring is not hard to achive , just taper the bar diameter as you would with a coil

[Roadman]

     This is an excellent article on the subject.    https://www.allpar.com/mopar/torsionaire.html

[CudaMoparRay]

Well that settles it, was thinking coil overs, but keeping it as is with torsion bars

[soundcontrol]

I was thinking of an AlterK setup when I started my project, but I decided to stick with the T-bars. I took into consideration exactly what CP said here, that the car was not built to have the force of the suspension on the inner fenders, I also read a tech article about it (forgot who wrote it now), but in the end I did not wanna make such a major change to my car. I trust that the Chrysler engineers know this stuff better than I do. And the Hotchkiss E-max Challenger runs very well with a stock setup so that was proof enough for me.

[Brads70]

When I first bought my car even before it was delivered I had intentions of cutting the front clip off at the firewall and building my own clip. HP2 and Neil talked me out of it . That and when I got the car it was so clean and rust free I just couldn't cut it up. I'm very glad I didn't cut it up and stayed with the stock design.  It was not a cheap but I finally have the handling I'm happy with. I had a few spare parts left over when I was done, trying different things. My set up is not " stock" per say but uses stock parts, basically the front end is very similar to the Chrysler kit car. I get a giggle out of people mindlessly following be into a turn. I usually don't use the brakes and often accelerate (which is the opposite of what it drove like stock)   then giggle when they get to a point and slam on their brakes because they can't drive the same.  Tires make a huge difference too. 99% of the Mopar crowd use BFG T/A 's or worce.... they are horrible tires for handling IMO. ( recycled hockey pucks! LOL)

[soundcontrol]

What tires do you recommend Brad?