Lowering upper control arms -Shelby Mod

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There are reinforcements that will not allow this mod unless you do some serious surgery... at least on my 73 there is. I made templates with the intention of doing it. I decided it's not worth it on our cars IMO.

 
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So did we decide this was something that benefits our cars? I don't want to drill holes if it isn't going to help.

I am thinking of going with TCP uppers, global west lowers, roller purches.
Why play games & mis match a bunch of stuff from different co's? stick with one system with all the components...from one vendor..If you want one of the best install the system I did..


 
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Id bought Open Tracker Racing parts also. Very well made and original looking, but with full roller bearings to prevent binding or squeeks. Installed with new Moog parts and the front suspension is the cheapest and best working part of my car. The guy there also said that our cars do not need the lowered upper arm. The geometry was all figured out by 71. But lower springs were a good idea because i have swapped a lot of iron out for aluminum.

 
I attempted this myself many years ago and found out what droptop73 said, there are reinforcements that do not allow without heavy modification. I drilled the holes on one side, installed the UCA, scratched my head, and aborted.

 
pro motorsport eng. has the kit for 7173 and i did my 71 . i also purchased the neg wedge kit to centralize the balljoint. you do need to pound flat a double panel below the UCA. no big deal, and with progressive rate springs

it greatly improved hard cornering.

 
I did the shelby mod, it wasn't involved at all. My car handles amazing. I have the pro-motorsports ball joint wedge thing. Don't know why anyone wouldn't do this.

 
Curious too... My global west setup just barely rubbed in the lower holes even with their spacer. As a side note, with no more rubber bushings in the front end, and roller perches, I actually have suspension travel now! No more inch or two of creak-creak.


 
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I have repop control arms I purchased from Canadian Mustang. They are stock replacement with delrin bushings. My car is at my friend's house in Charlotte, but I'm picking it up this weekend. I will try to take pics when I get it here and unloaded.

 
The movement in the 73 in that video would suggest the shocks are too soft. Seriously i have full Opentracker roller front end and my front end doesnt move that easily. Even if it compressed easily like a dirt track car the rebound is much too soft! On the street you'd want more compression dampening. And i have taken a good amount of weight off my front end.

 
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image.jpgI'm using these from SPC and there is no need to drill into the tower or shim ball joints.
 
I have never seen this thread before, seeing as it's really old, I want to address the question of the upper control arm drop. We do NOT recommend doing the Shelby drop or our dropped pivot shaft on these cars.

Why do we offer the dropped pivot shaft on the arm that fits 71-73? Simple, because it also fits a bunch of other cars on which we DO recommend the drop pivot. Which other cars? Mustang/Cougar 67-70, Falcon 66-70 and Ranchero to 71, Torino 68-71, etc.

About six minutes into the video below Jason explains that we don't recommend dropping the upper on the later cars. Then he says my name; I'm famous!

ALbrInnpoV8

 
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I did a DIY UCA lower on my car a few years ago. It turns in really well now and improved the stance. I have typed up the the full tedious details of the mod & have a few photos if anyone is interested?

 
Of course we are interested. There is no such thing as too much information. Well, there is sometimes but not on car related subjects. :)

 
Ok, well you asked for it!

A few years ago now I lowered the UCAs on my Mach1. Previously I had a '70 coupe on which I wore the outside of the tires down to the cords because of hard cornering. I became aware of the Arning drop but I did not know the 71-73 geometry had changed – it looks the same to me! I was inspired by availability of a kit for 71-73s in the NPD catalogue that stated the arm was lowered by 1.75". Living in the UK makes all parts from the USA expensive so I went for a DIY approach. I needed to replace the UCA shaft & bearings anyway. While it was apart I welded some reinforcement on the arm. I fabbed wedge plates for the ball joints from aluminium. This was the most tedious part of the job as I don't have a mill.



I then made an aluminium template that I could secure to the original mounting holes with studs sticking out to test the new arm location before drilling. It seemed to be ok. I had to do delicate surgery with a cutting disk to get the lower reinforcement out of the way. I welded it's lower edge down and added an additional reinforcement plate of 16 gauge which is also bolted to the original holes (not in these photos).

Drilling the new holes was an issue as the 9/16” hole went thru the edge of a layer of sheetmetal in the engine bay. I think I drilled thru 3 ½ layers of metal. The drill hung up on a weld on one hole, slamming my hand into the shock tower reinforcement and bending the drill shaft a bit. I had to fabricate stepped washers for these locations. I installed the arms with dampers (Konis off the 70 with top brackets to match) but no springs so I could test the full range of movement. On the left side of the car there is already a notch in the frame giving clearance for the dropped arm at full droop.



I had to cut and weld up a notch on the other side.



Even so I had to add 1” spacers under the top damper bolts to prevent the arms hitting the rails. Later I bought some of the taller early upper brackets (65?) and they worked fine. The Konis were sticky with age so I put on some KYBs later and was able to go back to the 70 upper bracket as the KYBs are shorter. I also had to weld a platform on the end of the UCAs to make a square contact with the bump stop.





The other point to be aware of is that the further the arm is lowered, the less suspension travel you have because the outer end of the arm gets closer to the bump stop (it has pivoted about the spring seat). The amount I lowered it is the absolute max with stock parts as part of the spring seat touches the top of the UCA at full bump and it cannot be relieved without major mods to the UCA.

Full droop:



Full bump:



Another issue that cropped up when I took it to get aligned is that the camber could only just be set to zero, probably because the lower mounting position is further out than the original and also because of the re-inforcement plate I fitted.

 
So as I understand it today, everything you did should not have been done given the car vintage. Not picking on you at all but just hoping to land on THE answer as I start to tweak my '73 Mach 1.

 

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