tubular lower control arms

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They're about 8 lbs lighter than the stockers, and allow for more suspension travel because you have more clearance to the bumpstop than on a stock lower.

As far as cost, if you can do the blasting and reinforcing, the tubular ones are about 4x as expensive. I just clean mine up, weld in the reinforcing plates, and swap them to new grease-able pivot pins and poly bushings. Powdercoating is totally overkill, they were bare from the factory. I just spray bomb mine.

Finally, about experience. I ran a set of these on my Challenger for a few years. They were built by CAP, which was bought out by QA1. CAP was known for crappy quality control and welding, and lo and behold, I broke a weld on one of mine. Well, fractured one. No catastrophic failure that led to a crash, I noticed my car was sitting low on the right front and found the cracked weld, which allowed the tubular LCA to bend enough to drop my ride height.

I'm sure that QA1 has done their homework, I think these were off the market for a couple years after QA1 bought CAP. Rumor was that they were re-evaluating designs etc. I'd have to compare a new set to my old set to see any changes, the pictures look about the same. But even if all they did was make sure all the welds were good they'd hold up fine.
 
I have a set on my dart. I bought them from cap. I still have to custom make a steering stop for them. I have only put aproxx 70 miles on them in the lasr 4 years so still to early to give a grade but i am always inspecting welds on my aftermarket suspention parts.
 
Darren said:
I have a set on my dart. I bought them from cap. I still have to custom make a steering stop for them. I have only put aproxx 70 miles on them in the lasr 4 years so still to early to give a grade but i am always inspecting welds on my aftermarket suspention parts.
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Good luck!

I probably put about 35k miles on mine before the failure, daily driving my car over the course of about 4 years.

If I had a set that weren't bent, there are a few areas I'd gusset to improve the strength and re-weld before I ran them again. It's not so much a design issue with them, CAP just built them with crap welds.

But since one of mine is bent, and I'm not keen on straightening it and running it, I'll be sticking with reinforced stockers. Don't care about the weight, but the extra 3/4" or so of suspension travel would be nice for my lowered cars.
 
You can gain the suspension clearance by working stock lowers. There's NO WAY in hell I'd spend that much on lower control arms.
 
"Tubular" - anything is the must have today. It used to be "billet aluminum" - anything. It doesn't appear to me that these would be stiffer in aft-fwd bending than factory LCA's with a lower stiffening plate.

Indeed, I don't know why people think they need a plate, but perhaps I need to read more. The LCA's purpose is to locate the lower ball joint. It needs to be stiff in the up-down direction to apply the force of the torsion bar. The strut rod locates the ball joint fwd-aft, so I don't see why the LCA needs to resist fwd-aft bending. Indeed, the bolt bushing allows it to bend fwd-aft anyway, no matter how stiff it is.
 
BillGrissom said:
"Tubular" - anything is the must have today. It used to be "billet aluminum" - anything. It doesn't appear to me that these would be stiffer in aft-fwd bending than factory LCA's with a lower stiffening plate.

Indeed, I don't know why people think they need a plate, but perhaps I need to read more. The LCA's purpose is to locate the lower ball joint. It needs to be stiff in the up-down direction to apply the force of the torsion bar. The strut rod locates the ball joint fwd-aft, so I don't see why the LCA needs to resist fwd-aft bending. Indeed, the bolt bushing allows it to bend fwd-aft anyway, no matter how stiff it is.
Click to expand...

The load forces from the wheel are applied fore/aft (picture hitting a chuckhole or applying the brakes). This creates a bending moment around the LCA end of the strut rod, which acts as a pivot, which then transfers fore/aft forces to the LCA. Wheel moves (or tries to move) rearward, it pushes forward on the section of the LCA between the strut rod and pivot.

If I find the pictures of my bent LCA from where I hit a curb, it will be perfectly clear, and that was why I added the plates to my LCA.
 
My drag Demon must have been a wheel standing machine back in the day. The LCAs on it were spread apart and the rotating torsion bar transfer thingy was really loose and sloppy. I now have sand blasted 43 yrs of grit/gunk from another set and welded on the plates then painted them. Had the pivots plated and put in new bushings. Nice and tight now.

I may go with tubular uppers if the car launches OK, but would not use tubular lowers. Just me.
 
jos15700,
Those must have been tremendous forces since the strut rod attaches to the LCA very close to the lower ball joint. It doesn't quite make a triangle strut arrangement though, so I can see where the LCA can pivot around the strut attachment point. However, if the LCA didn't distort and relieve some of the force, the strut rod might have pulled thru the K-frame. That probably happened in my 65 Dart, since there is a thick welded plate over the original strut rod attachment. That is much harder to fix than replacing the LCA, and the LCA gets destroyed in either scenario. I wonder if the engineers designed it to fail like that to protect the K-frame.
 
Watch this video...

[ame="http://www.youtube.com/watch?v=Nwes-SP8u4w&feature=share&list=UUqvjc-8llEE-JKNFYw30-NQ"]Control arm repair - YouTube[/ame]
 
I will do anybody's arms (I've got some spares, but I don't tend to take the time unless there's somebody waiting for them). Every arm I do goes through my hot tank and gets bead blasted. I do have one last set of plates before I need to order more... $125/pair plus the bushing...that includes removing the slop, if necessary.
 
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