Check Out My Control Arms

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BrianT

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In a previous thread it was pointed out to me that the upper control arms on my 70 Duster are cut down B body arms and that I have B body brakes also. I was told it was an old school trick before the big bolt pattern brakes became more common. Here's a shot of what I'm working with.

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I am wanting to replace them but I'm not sure where to start. Since it has B body calipers, am I correct to assume that these are B body spindles and rotors?

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I plan on buying new control arms but want too make sure that I'm getting the right ones. Will aftermarket A body upper control arms play nice with my B body spindles? These are the ones that I am currently leaning towards.

PST Adjustable Control Arms

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Thanks in advance for any help and guidance.
 
big bolt A body uppers will (or should) play nice with the rest of your set up.

you have a # on the spindle?

* i only say "should* because after seeing welded arms who knows what other chicanery may be nigh
 
So those are single piston calipers, pin-type, and would have a 2.75" piston. You'd have B-body spindles with those. Depending on the year of the spindles they may have the smaller wheel bearing set up used on the '70-72 B/E bodies instead of the larger wheel bearings found on all the 73+ spindles.

Those would be large upper ball joint control arms, so, as long as you get large upper ball joint A-body UCA's you should be fine.

As far as the PST adjustable UCA's, I will say this- I'm not a fan of heim joints on the street at the UCA. I've run them, my Hotchkis UCA's on my '72 Challenger had them. The first set only lasted 7k miles.

The other thing is, that style of adjustable arm requires removing it from the mounts to adjust them. It can make the initial alignment process somewhat tedious, because if you have to adjust the lengths of the heims you have to pull the UCA's out of the mounts every time until you get close enough to work with the camber bolts.

Depending on your use of the car, I would either use a set of QA1 UCA's, which are not adjustable but have additional caster built into the arms 1974 PLYMOUTH DUSTER QA1 52301 QA1 Mopar Control Arms | Summit Racing

Or, go double adjustable, so you can adjust the UCA's without removing them from the mounts SPC 2.0 FORGED UPPER CONTROL ARM - Bergman Auto Craft

I do miss the gen I SPC's, which were fully adjustable without the forged section and cost quite a bit less. @BergmanAutoCraft
 
Those are not B body upper control arms. These are.

UCA 1A.jpg


It would be really difficult to modify them to fit an A body. They are wider from bushing to bushing and the distance from the mounts to the upper ball joint is longer too.
 
I`d ask how long those have been in service and if its been years and the welds look good, I`d run that system till the cows come home, but I`m the thriftmaster:)
 
They have been that way since the "restoration" was done in the 90's but I am getting ready to put a serious engine in and plan on beating on the car regularly. I probably don't need the double adjustable arms but I definitely want something that's not hacked together. These were listed last night here.

PST G-Max for Sale
 
nice....and a great price, but they will not give you additional caster (most are looking for) without putting the suspension (UCA) in a bind.

check out the HDK chromoly UCAs pictured. Adding caster is obtained, regardless of who makes the UCA by moving the upper ball joint rearward. HDK does this by combining aluminum spacers with adjustable poly ends (NEVER a failure) to easily place the ball joint in your desired location.

HDK exclusive upper ball joint receiver captures the dust boot keeping the lubricant in and the road grime out.


from the HDK install tips..........

You received the latest version of the HDK upper control arms with the cantered receiver that help the dust boot stay centered and the dust boot tucked into the receiver. Besides the HDK stickers to mark which side they install on, there is a single centerpunch mark on the top portion of the right / passenger side receiver and a double punch mark on the left / driver side.

If the UCAs are installed as shipped with

one thick spacer to the rear of each poly end.............................3.0 positive caster (manual steering)
narrow spacers on each side of each poly end.................4.5 positive caster(aggressive manual steering)
one thick spacer to the front of each poly end..................................6.0 positive caster (power steering)


I still like to use the adjustable poly ends to make sure when doing the initial alignment (before it goes to the alignment shop) I am positioning the OEM cam adjusters in the middle / center position. Of course the key is fluid motion of the assembly at your desired caster / camber specification.

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I just mentioned to my wife that a pair of tubular upper arms (exactly what you need) are available here, less than half price. Good luck
 
No way I would use any suspension parts with hiem joints. I've never seen any that were heavy duty enough for substantial street use.
 
They have been that way since the "restoration" was done in the 90's but I am getting ready to put a serious engine in and plan on beating on the car regularly. I probably don't need the double adjustable arms but I definitely want something that's not hacked together. These were listed last night here.

PST G-Max for Sale

Those look pretty much identical to the set I had on my Duster before I went to SPC GenI's. With a set of moog K7103's in them I was running as much as +8° of caster with them at one point. Never had any binding issues with the UCA although the tight "V" shape does sometimes require notching part of the UCA mount, it depends on how much of an "ear" they left on it on your particular car.
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No way I would use any suspension parts with hiem joints. I've never seen any that were heavy duty enough for substantial street use.

The heims at my QA1 adjustable strut rods did 70k street miles with no issues whatsoever, they're still tight. On the Hotchkis UCA's on that same Challenger I was only getting about 7-10k out of the UCA heims before they were worn out.
 
Your call to make Brian....
If folks have not already been asking for them privately, be sure to offer these custom arms in the classifieds (scrap $ plus shipping?)
 

I’m taking them off because I feel that they may be unsafe. I couldn’t sell them to anyone and have a clear conscience.
 
If you want to change spindles to get bigger inner bearings, you can use 73 & up A body, or 73-74 E body spindles. You should be able to bolt your existing caliper adapters and calipers right to them and not even have to bleed the brakes unless you undo the calipers in the swap. I prefer pin type calipers like the ones on your car now. I have used later A body spindles with 11.75 rotors with pin type caliper adapters from late B bodies on two cars so far. Stop on a dime and give you 9 cents change!

I think you're of the right mindset on the Frankenstein UCA's. I'd cut those things into 6 different pieces and throw them in 6 different dumpsters so they could never be traced back to me....lol.
 
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