Anyone interested in bagging their 70 C body stub frame without removing the torsion bars or the whole stock front end?

ACR Nick

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Im currently restoring a 70 fury 3 convertible and I noticed that there was not a kit made specifically for the C body stub frame, nothing that works in conjunction with stock parts anyway. I have seen whole kits that drastically change the suspension which delete the torsion bars, changes the stock steering, upper and lower control arms, different bump stabilizer thats usually some type of coil over replacement.

The point though is that I've taken a very universal kit and figured out how to mount the bags in such a way that with the proper fitment, has some holes drilled in the upper control arms for the airbag base on the front end and Ive fabbed a support that does not rub or otherwise interfere with anything on the front end. You need 2 inch wheel spacers, but on stock sized rims and white walls, you dont have to modify the body at all. The wheels have a sunken in look from the factory and the spacers do wonders for this cars profile and stance on the road. I know some of you cringe when hearing, 'stanced,' but i promise you its nothing like your grandsons honda. I just mean it gives the front and rear a much needed wider profile with the stock spacing that makes the wheels look like they're hiding.

For the rear, we are eliminating the leaf springs in favor of a 4 link suspension kit that's a brainchild of a collaboration between my pops and I thats based on another very universal 4 link kit. The biggest modification here is installing the brackets that hold the 4 link bars and relocating the e brake braket because its in the way on the drivers side. I'll post pics of a finished product in a few weeks. Im just seeing who has a c body, stub frame and may be interested in something like this.

Ever since starting work on this car, I've found that finding anything for this stub frame that is the backbone of the last big convertibles like the 70 fury 3 verts and the chrysler 300 verts is more of a 'good luck,' type of situation, or use your brain, welding machine and 4 and a half inch grinder and figure it out.

Oh, admittedly, I am going to have to modify the inner fender wells to fit the top side bag brackets but that isnt anything major structurally.

I just knew the moment that I looked at this stub frame that it wasnt going to be a good idea to completely eliminate the torsion bars, and being as how this particular fury took a pretty hard hit on the drivers side long before I was born, I was hesitant to order a suspension overhaul kit that was likely going to give me fitment issues anyway. I ended up reinforcing the main frame tubing on the drivers side, so the design I came up with is made to fit the actual dimensions of the frame its being fitted on.

Well, my painter has the car now and I'm currently refocusing on getting my machines set up to sew 4 cows worth of white leather into a totally refreshed, brand new interior.

Putting out some feelers on interest in something like this and also hoping someone has a good set of 70 fury 3 tail light covers for sale, or just a good drivers side light cover.

Pics incoming once my guy is done with paint! Excited to see thia old bird coming back together!

-Nick, ACR
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Watching with interest...good luck finding those tail light lenses. How much will the 4 link intrude into the trunk? What color are you painting your vert?
 
Watching with interest...good luck finding those tail light lenses. How much will the 4 link intrude into the trunk? What color are you painting your vert?
The answer is simply that it doesn't. Ive fabbed brackets that bolt through the unibody frame almost exactly where the the linkage splits the e brake line to route to each drum. Those two outer link bars go from there on each side to a bracket that mounts almost exactly where the the leaf springs were joined to the axle originally. For the other two links they sit further above the other two brackets, and are also bolted directly to the uni frame and plated on both sides for extra structural support. Those two angle straight at the differential and connect to brackets that nearly encapsulate the entire stock diff. The bracket slides on to the diff using the top 4 bolts of the diff for positioning only and that bracket is fabbed in such a way that it can be removed if maintenance is required on the rear. So basically two almost run parallel to the length of the vehicle and the other two angle straight at the diff to cover all directional torque pulls under acceleration.

The front is also designed with maintenance in mind so that youre able to access the ball joints on the front end and is also able to be totally unbolted if you should need to do so.

Im hesitant to sell an at home kit based on the fact that everyones c body will have its own unique history and it would be a waste of time to attempt to find a universal one size fits all instead of tailoring the fitment to the actual dimensions of each individual frame but i am located in Houston and would be happy to get this done in house for anyone who wants a setup like this. Theres just certain aspects of fitting and fitment that needs to be exact for structural safety and I cant expect someone else to think within my design to account for all of that in their driveway or even at another shop. My pops is an engineer with 40+ years of experience in old iron and I also have worked on old iron for most of my adult life. At 35 I can honestly tell you that my capabilities extend well beyond parts changing and trouble shooting and Ive rebuilt many engines that happily and currently scream wherever they go. I also have an absolute hatred for doing something twice when it deserves the care to do it right the first time. In my experience, there are certain things with old iron that you dont get the luxury of screwing up once. The army taught me the phrase of, "First time go," and I try to live by that within my business.
 
Heres some old pictures I took during the fab work. I dont have a pic of how i solved the bag assembly and support over the rear axle but after removing the leaf springs in favor of the 4 link and bags, Ive elected to replace the air shocks in the rear with an oem replacement for additional bump support and strength on the rear end. Also slid in a picture of the rebuilt 383 motor and valve covers and air breather thats going with it, the old stock valve covers are on it just keep it protected while waiting to be installed after paint. Went with a weiland intake and 4 barrel carb with a slight lobe height increase on the cam for a tasteful power upgrade.

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Technically its a 6 link rear end counting the two air shocks with no trunk intrusion besides the stained ebony wood that ive mounted all the airbag hardware to that sits neatly next to the spare tire in the trunk. Ive blocked the leaf spring bracket to the height of the stock leaf springs to maintain that bracket fitment because the air shocks bolt directly to that bracket.
 
Alright gentlemen, its time to go and earn my food today and get back at it. A couple more pics of a different project, not a c body but certainly a close relative and the lucky recipient of the 426 hemi that im verifying clearances and machined sizes for thats going to replace the stock 318.

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Everything pictured is fabbed out of 1/4 inch steel or better. Ok, I'm getting to work because I could happily talk about old iron all day without taking a breath.
 
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Somebody over on FreakBook did it quicker...

1968 Plymouth Fury III 4dr HT.005.BAGGED.jpg


Why oh Why do all that work and not spend any energy cleaning the frame?


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So the ACR kit will use airbags but still keep the torsion bars, correct? And it looks like the bag will mount on top of the UCA? Doesn't look like it could mount underneath, as it would hit the UPJ and also the shock tunnel (circled). So there's an upper mounting fabrication to ground the airbag?

@ACR Nick I won't be a customer as I have a low-mile rebuild using FirmFeel torsion bars. But I love seeing other folks creativity and ingenuity. So I'm looking forward to seeing what you come up with.
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And the greasy gold 68 has no shock absorber. Can't tell if it's still using the torsion bars. I wonder how well that suspension works.
 
Looks to me that the greasy gold unit has had surgery in the upper control arm. And how the UCA attaches to stub frame.
The torsion bar needs to stay to support the lower control arm.

I'm a long ways from bagging a C, but my limited intelligence kinda tells me a ford crown vic or dakota front clip grafted to original stub or modified to fit the car like original stub does might be worth investigating.
Or pay the big money and get a custom stub if they are still available.

I do enjoy seeing people create and build stuff
 
The problem with grafting a whole front clip isnt in suspension fitment, the *** pain that develops shows up when youre trying to maintain proper body lines and panel gaps. Thats why, in my opinion, its worth maintaining as much stock components as possible, especially the original frame.
 
Looks like you were thinking outside of the box. That is a very interesting set up. I was wondering why you would need to modify the inner wheel wells, and what that plate on top of the UCA was all about. It's starting to make sense now.

I look forward to seeing progress, and some rear suspension shots, not to mention the new interior. Keep up the great work!
 
Looks like you were thinking outside of the box. That is a very interesting set up. I was wondering why you would need to modify the inner wheel wells, and what that plate on top of the UCA was all about. It's starting to make sense now.

I look forward to seeing progress, and some rear suspension shots, not to mention the new interior. Keep up the great work!
The job sort of required me to think outside the box. He wanted to feel and benefit from some modern quality of life upgrades but the fact this car belonged to his dad who passed away also made keeping the car as original as possible a very important priority.

Wait until you see the 4 link setup in the rear. As much as I'm honored to be trusted with restoring something this priceless to him, I am happy for a much needed touch of modern that comes with deleting the leaf springs and widening the wheel base with the 2 inch spacers all around.

And yes, on stock rims and whitewalls the rear clears on 2 inch spacers. Its close, you have about a half an inch at most from the outside of the tire but thats all you need. The wider profile definitely suits a C body, im very pleased with how much of a subtle impact 4 inches of extra wheelbase provides.
 
Here's some more pictures of the FB lowering job. I just sped'red through the comments, most of the latest talk was about the rear end. aaaYup no shocks, must ride like a champ!

Progress on my bagged ‘68 Fury III.jpg
Progress on my bagged ‘68 Fury III_REAR.jpg



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I've given this a bit of consideration, whether to say any of this. I'm not trying to be a debbie-downer know-it-all - but I now see some things I didn't notice previously.
Because it uses mostly OE parts, it looks like a mild modification - but it's really quite different from original.

As @rd92west mentioned, the LCA is no longer being supported completely due to no T-bar. It's gone from being in 'double shear' of sorts to being cantilevered on the pin. (the T-bars would have provided some radial support due to the length of the hexes in the sockets)

But more importantly, nothing constrains the LCA from moving rearward except the integrity of the LCA bushing's rubber on the shells. (originally it was held forward by the pre-load tension of the T-bar in 2 hex sockets + the shear of a small retention clip at the rear bar socket. A custom-machined bolt/pin could hold the LCA in via the hex socket but the pictures above suggest a factory pin is in place.

Another thing that's now totally changed is the force-loading.

Originally, all the vehicle weight and dynamic loads were grounded thru the LCA, its pin, the engine crossmember (via the LCA pin), rear T-bar crossmember, and the bottom half of the spindle (out to the wheel). The UCA mainly locates the upper portion of the spindle for proper steering alignment under all conditions - but it bears minimal vehicle weight. The shock absorber loads are 100% thru the LCA to the frame. (the strut rod's function is unchanged with the airbags)

Now all vehicle weight loads are being grounded thru the UCA/brackets and the fabricated bracketry for the top of the airbag. The upper bracketry is fixed, constraining the airbag radially and vertically at the top, but the 2 UCA cam-bolts and bushings are the only thing constraining it radially at the bottom. The loads at the mating faces between the bushing shells and eccentric washers to the UCA brackets are likely still OK (that's double-shear on a bolt). But the loading against the pressfit of the outer bushing shells into the UCA is increased, as are the loads on the UCA brackets themselves. The bracketry to locate the airbag on the LCA hasn't made it stronger - where the added metal stops (the green lines) is still the original cross-section. Shock absorber loading is now going down thru the spindle, which it wasn't before (although this seems not as significant).

Logically an alignment hasn't been done at the time of the pics, but the apparent angle between airbag travel and spindle travel might cause further load at the rear cam bolt. And what does heavy braking add to that?

This is a departure from the factory engineering design so original Factors of Safety cannot be depended upon (as we often do when we modify our cars). Even the factory engineers couldn't analyze and test everything - it is known that some M-body copcars had alignment issues due to the UCA brackets bending on the frame under urban patrols on rough streets.

I'm not trying to be an expert testifying that it won't work, I'm just providing food for thought. I do suggest you have this car brought in periodically for a close inspection, and after any 'heavy usage incident', to ensure nothing is degrading. It's your prototype, you gotta keep an eye on it - don't depend on the owner/driver to contact you if he notices something wrong, he may not be savvy enough. (it's not a gearhead-enthusiast thing, it's a thorough-technician thing)
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The only proble with what youre noticing is the fact that all of the bolts arent in the base of where the bag sits. They were removed to pivot the base upwards so I could grease the ball joint. Also, the torsion bars still bear a load in an extreme bump situation but are set to only support any weight if the bag loses all pressure.

Its understandable that I need to closely monitor and check this setup after a few weekend uses of the car, which is why I will be getting it back after a month or so of what he considers normal use, and then every quarter for the next year. It wont be far from my eyes anyway, i have two more vehicles to do for this guy aftet this is finished. Before even giving it back to him I will be putting about 150-200 miles of varied use in it personally to see how everything handles.

Another thing, the torsion bars used to completely set the ride height and absorb the shock because whats equipped that looks like a shock absober is nothing more than a bump stabilizer. I can take the old one or a brand new oem part, brace one end on my chest and fully depress it just by squeezing it. Despite the fact that im not weak or lacking in any category of physicality, but I absolutely could not do that if it was an actual shock absorber or any sort of part meant to be load bearing.

If im honest, the only reason im leaving the torsion bars in is because in this particular application of a c body, its equipped with a stub frame due it being a convertible and it absolutely ends at the crossmember. If removed im predicting an increase in feeling a jolt when shifting out of park and I dont want uneccesary wear on the motor/trans mounts. The torsion quiet frames extend beyond the crossmember for another 16 to 18 inches and provide a little extra support on the cross member just by the frame being longer and not ending at the crossmember.
 
Also, you mentioned double shear. To my knowledge that only occurs when you add something that physically attaches to the bolt that is used as a pivot, in this case its the rear cam bolt. The bag base sits on the upper control arm and is the primary reciever of the downforce being applied to set ride height but I dont think that is causing what youre suggesting. I would have to add something that actually pivots in the same cam bolt outside of the normal degree of travel for that to cause double shear. I think you may be mistaken there.

Also, the red line youve drawn to show the spindle angle is simply how this car is, the entire upper control arm on these c bodies are all canted. They dont sit parallell to the ground. Thats the function of the ball joint to hold that angle.
 
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