Loosing the torsion bars and replacing the shocks with coil overs?

Mr. Nitro

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1967 Plymouth Fury III

I am wondering if anyone has tried or thought of replacing the stock front shocks with coil overs. I would think that you could loose the torsion bars this way and make a ton of room for headers and such. It would require fabbing a spring can in the frame rail in the location where the top of the shock mounts now, but I think it is do-able. Any comments?
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There is not room for that unless you do a major frame modification.

If you do not think that the torsion bars are stiff enough, go to a heavier set.

Dave
 
By observation, many people look at the space the torsion bars take up as a big negative. They always mention "room for headers", BUT that does not mean that headers for Chrysler products do not exist at all! Headers have existed for Chrysler products in spite of this alleged "space issue". So, that argument does not work.

No real need for "undercar headers" on anything other than a full-race car as they can be too prone to dragging or getting damaged during normal driving. For a street car, the extra power they might produce is really not needed or could be compensated for with better chassis dynamics to better plant the rear tires (which is pretty much already there in the Chrysler rear leaf spring suspension design).

As to "coil overs", if you look closely, you'll see that what Davea Lux mentions is completely accurate. The existing "shock tube" limits the size of the shock absorber's inner piston to 1" diameter. Which means that "HD" shocks have stiffer valving in them rather than just larger pistons (as the rear HD shocks have).

Coil overs might offer advantages in ride height and ease of changing spring rates, BUT do you really need those things on your car? Circle track racers regularly change springs for each track they might race on, not to forget the ability to stiffen the spring with a special tool to compress the outer spring. The ONLY real advantage of coil overs would be the capability of compressing the spring and not changing front end ride height too much, whereas when more pre-load is applied to a torsion bar with the same weight being supported, the front end of the car rises as a result, plus making the ride a bit stiffer, too.

On the newer vehicles with front coil overs OEM, to me they don't ride very well due to the dynamics of a stiffer spring that the shocks/struts must control with stiffer valving and such. But as younger generations have grown up with that "ride", they consider it "normal" as others just don't care. Those OEM coil overs are probably there to save some money in assembly labor for the OEMs rather than how well they ride, I suspect.

I can understand your desire to "make things better", but in this case, to me, that's effort that could be used to re-wire the charging system (search "cbarge" "ammeter bypass" in this forum) or things similar to making the car really better and more efficient/reliable. Without ruining some excellent original engineering in the process. Designing a larger "shock tube" as a "drop-in" swap might be good, for many reasons, other than coil overs.

Many thoughts,
CBODY67
 
The inner fenders are not designed to take the weight of the car. They are strong enough to hold the shocks on A, B and E bodies. C bodies have the stub frame but it seems like way too much trouble to make it work.
 
For the effort to modify the frame one might be better to fabricate an entirely new stub frame, one of the benefits of the C-Body.


Alan
 
From what I've seen since the whole ProTouring stuff started, is that many people are used to dealing with GM (especially) and some Ford vehicles, which have front coil springs. That's what they consider "normal", so the Chrysler torsion bar set-up is "weird" to them. They look at them as a hindrance more than not. Taking up way too much space in the chassis, to them. But space they won't be using anyway (with the issue being "header clearance", typically). AND considering that many street rod chassis (think "Early Ford V-8") have even more space issues, requiring block-hugger header/exhaust manifolds, to me, these issues might tend to indicate a lack of real problem solving capabilities or knowledge what other segments of the auto hot rodding hobby have to deal with.

Perhaps this is something of a "generational issue"? Where it takes a front end with coil-overs and 8 degrees of positive caster just to go to the corner store for some bread? Or a cross-bolted main engine block to do the same? Perhaps they need to get out of their comfort zone, take off their blinders, and understand why some of the newer stuff is not always better? They might not know that Chrysler's front end geometry (negative camber gain for the outside front wheel in a corner dates back (in Chrysler products) at least to the 1957 model year, for example. Ages before Ford and GM started to use it!

One other thing, to me, is that with the proper tools, a torsion bar is pretty easy to change. But they have their quirks which must be known about and respected. PLUS the rear mount crossmember is allegedly a very low-stress part of the car, unlike the front crossmember on a coil spring suspension vehicle where all of the spring stresses are concentrated in that ONE area where the control arms are located.

To me, the reason that many rack-and-pinion steering cars were noted to have better steering response is that they are mostly fron-wheel drive, with strut suspensions, so with all of the front cornering, braking, acceleration, being initiated in that ONE area, the front structure of those cars need to be stiffer and more substantial to do all of that. As CAR LIFE magazine noted in a road test of a '65 Satellite, the stiffer unibody construction makes steering response better due to the stiffer structure the steering components is attached to. A side issue is that they are "rear steer" and do more perfect Ackerman angles of the front wheels in a turn.

Y'all enjoy . . .
CBODY67
 
I don't get it. If you want to go faster, buy a new Kia. Almost any new car is going to be faster than our land yachts.

Tesla 0-60 in under 3 seconds
Kia Stinger 4.7 seconds.
Hyundai Ionic 3.4 seconds
Even the huge Hyundai Palisade 8 passenger SUV is 6.3 seconds.
I guess we can still beat the least expensive car in USA. The Nissan Versa is 10 seconds....but it'll be close!

Just my opinion but your Fury should be restored to the comfy suspension that it was born with. Modifying never works as well as most people think, however if you want better handling and braking, then there are ways to improve what you got, as others above has stated.
 
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One thing I've noticed is people talk about these coil over stub frames, but I have yet to see or hear of anyone pulling the trigger on one.

Not judging and I'm no "purist". Just an observation.

Regarding the OP's question, the shock mounts aren't up for supporting the car (as mentioned). Nothing has been said about the lower control arm mounting either. The LCA depends on the torsion bar to support and help locate the pivot point. The LCA uses the fixed rubber bushing rather than a free moving pivot, so all of that would have to be taken into account and fabricated. Without the t-bar in place, the LCA will just kind of flop around.

In other words, it's not as simple as bolting up a coil over shock and knocking the t-bars out. When all is said and done, IMHO, there won't be any improvement in the suspension geometry so the only plus might be more header clearance. I don't see that (header clearance) as a big need.
 
The other bummer is we have surprisingly short front shocks and limited front end travel on our cars. I agree that retrofitting something is not going to be easy, even a Mustang II style front I don't think would fit without a ton of work. Maybe try to retrofit a Crown Vic front frame section?

The header clearance is definitely tight and worse than a B body on C's, no way to argue that. I don't know how they manage to have less space between the block and the torsion bars, but they do. I'm putting a TF 270 headed, roller cam 540 in my car hopefully at the end of this year when the engine is done - I definitely wanted bigger headers than the 1 7/8" TTI's but there aren't any options, it's definitely a limiting factor for horsepower between not being able to fit larger primaries and also not accomodating the raised exhaust port heads on the market. A set of custom headers could solve it, it would just add 3-5k to the cost of the build and they'd have to be slip fit to get at least one tube on the outside of the torsion bar on each side.. Being realistic, if you're talking about building something that makes 800+ hp on motor and you need > 2" primaries, we're using the wrong cars to start with, and if you want to be that serious it should have a tube front end anyway to help save a crapton of weight.
 
In one respect, it should be remembered that when the basic architecture was designed, probably in the middle 1950s, NONE of those issues were considered OR even existed back then.

Back then, too, "ride height" was approx 1/2 of total wheel travel, which was usually about 6" or a bit more. Modern coil-over front ends have very little compression distance and more extension distance, rather than "in the middle", by observation. Where any compression puts the lower control arm against the bumper and it's common to see cars and pickups get the front wheels off the ground after exiting even a mild dip.

There are MANY things Chrysler products are very good at doing, but trying to re-engineer them to do "GM things" (as many perceive to be desired, for various reasons) can end up costing many times what the car is worth AND destroying ANY real value the car might have (other than for body parts and such).

IF a Chrysler product is desired, then look at some of the pre-'57 full-frame cars and modernize their front ends and snake headers between the narrower frame rails. That MIGHT be a better option? Do a stroker LA or a Gen III Hemi, ZF 8-speed, fully-current EFI and spark control, with an upgraded suspension might get many just where they want to go, but would need to adapt the circular gear selector to replace the TF pushbuttons. Or rig a LX center console and seats?

Just some thoughts,
CBODY67


CBODY67
 
Additionally . . . I also suspect that many who perceive they need coil over front shocks have not ventured off into "Uncle Tony's Garage" YouTube channel. I ran across a video he did 3 years ago (from now) titled "What Makes Mopars Awesome". In this video, he details and explains Chrysler torsion bar/leaf spring suspension systems, front and rear, AND why they are better. From the design and also the performance aspects.

As to "short shocks", I don't see how that can be an issue. It's the valving inside the shock that does the work, not the length of the shock. Either one can have stiff or soft resistance in either direction. It's the resistance portion that determines what the front HD and non-HD shocks do, rather than shock abs piston diameter. PLUS how this valving can interact with spring rates, just as with every other shock absorber on the planet.

So, check out Uncle Tony's video mentioned above. Just because GM did something "normal" does not mean it's the best way to do it. In many cases, it was about costs and simplicity rather than not. Which might even make "normal" into "mediocre".

CBODY67
 
1967 Plymouth Fury III

I am wondering if anyone has tried or thought of replacing the stock front shocks with coil overs. I would think that you could loose the torsion bars this way and make a ton of room for headers and such. It would require fabbing a spring can in the frame rail in the location where the top of the shock mounts now, but I think it is do-able. Any comments?View attachment 663995View attachment 663996
1967 Plymouth Fury III

I am wondering if anyone has tried or thought of replacing the stock front shocks with coil overs. I would think that you could loose the torsion bars this way and make a ton of room for headers and such. It would require fabbing a spring can in the frame rail in the location where the top of the shock mounts now, but I think it is do-able. Any comments?View attachment 663995View attachment 663996
Thanks for the input. But I think most of you are missing my point. Point being to do something different and if anyone had ever tried it before. I know all about the work that would be involved. I did this resto mod upgrade on my 67 Barracuda 21 years ago. There are many things on this car that "they say can't be done", but I can tell you that it is a great car and I have over 30,000 miles on it since I did this upgrade. Let's keep the conversation going. I have not decided what I am going to do with the fury just, just looking for input. Thanks
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Nice looking car!

Nice looking installation, too. I suspect your car was a LA motor car, to start with?

In one respect, you are already doing something different. You have a Chrysler product.

CBODY67
 
I for one would like to see a car completed with this conversion.
If you decide to continue, PLEASE, please post pictures of your progress as you go.
Will make for some great fun to watch and some "critiques" as you go along.
 
One thing I've noticed is people talk about these coil over stub frames, but I have yet to see or hear of anyone pulling the trigger on one.
Possibly because they get in over their head, and nobody wants to admit they've ****** up their car, can't afford to pay a pro shop to fix it, and can't sell it for anything other than a non-rolling parts car. After we gave them all the reasons not to do it. (sorry about the f-bomb, but that is the most fitting word)

1967 Plymouth Fury III

I am wondering if anyone has tried or thought of replacing the stock front shocks with coil overs. I would think that you could loose the torsion bars this way and make a ton of room for headers and such. It would require fabbing a spring can in the frame rail in the location where the top of the shock mounts now, but I think it is do-able. Any comments?
Anything can be done, one must decide if the effort is worth the goal. Or what the true goal is. You've given us 2 different goals.

Your first goal was header clearance. Get a set of TTIs, Hedman shorties, or custom-made. Or extrude-honed HP manifolds. Much less effort and expense.
Besides, you still have a huge PS gearbox there taking up space that coil-overs won't change. Firm Feel has all teh parts to make it a great-handling car with a stiff ride like a modern car.

...But I think most of you are missing my point... Point being to do something different and if anyone had ever tried it before.... There are many things on this car that "they say can't be done"...

If the goal is to be able to prove others wrong and say 'look what I've done', to win approval and admiration from strangers, or just to have personal satisfaction - only you can decide the value of that.
 
What I want to see is some conversions over to rack and pinion. The rest of the car is fine.
 
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