Anybody here ever shimmed their upper control arms?

[Flatback72]

Anyone here ever used shims behind their control arms?

To recap my earlier thread, I was trying to find solution to my vibrating car problems, so I took my car to the local suspension workshop (turned out to be a separated gearbox mount).

As mentioned in that thread, to get rid of the infernal squeaking I had swapped out my standard upper control arms with aussie Falcon control arms with urethane bushings, only to find that the urethane ended up squeaking just as much. I was discussing this with the bloke at the suspension workshop and he told me they had in stock some change-over UCA's with rubber bushes, so I bought them on the spot because from experience with Falcons I know the rubber bushes never squeak unless the rubber becomes old and hard.

But back on subject, the bloke selling me the UCA's gave me a couple of shims (0.116" thick) and said if I put one each behind the front stud on the UCA's it would increase my caster, and combined with the caster generated by the caster rods it would give me excellent straight line handling out on the open road. I guess the theory is that by building in caster to the fixed setup, it will give more flexibility to the adjustable caster rods without having to pull the front wheels too far forward.

The bottom line though is that I am reluctant to use the shims as I don't really want to move away from Henry Ford's factory specs, but wondering if anyone here is using shims in the same way as described here, and if so what are your thoughts on this?

 

[73mach1]

I did it to mine,it's just a way to get a little more camber without taking it all from the lower control arm and getting your tire to close to the front of the fender.

 

[tempestairbrush]

I have included a good circle track article that goes into great detail about camber/caster good extra knowlege on what exactly they are to help you out. Front end setup is really important in short track racing and i recheck and readjust my race cars caster/camber settings every weekend. The princpales are the same, except you do NOT care about the caster split portion of the article or your car will only want to turn left. You want everything balanced on both sides. The more shims you put in the front studs the mose caster it will give you and will help the car drive and track straight, however if you do go too much or your stearing wheel will be slugish to return to center when you let it go comming out of a turn. One shim won't make that much of a difference and i would say go ahead and try it and see how it feels, Minus having a camber/ caster gauge or bringing the car to an alignment shop everything you do is a shot in the dark and may not even now be in the factory specs of how Ford made it. One last thing to think of is caster settings have a direct affect on camber and toe settings, even if they are small amounts so where that shim may help you there it may throw off the other settings.

http://www.circletrack.com/chassistech/ctrp_0801_caster_camber_settings/

 

[mustang7173]

Hello tempestairbrush,

Just printed out your recommended article. Thank You! I took a look at your 72 mustang build and I am amazed how the forum members put a lot of work into bring these mustangs and back them to life. Nice work!

mustang7173

 

[tempestairbrush]

Glad the article helped you out and thanks for the encouraging words about my build, hopefully in a few months it will be back on the road again.

Hello tempestairbrush,

Just printed out your recommended article. Thank You! I took a look at your 72 mustang build and I am amazed how the forum members put a lot of work into bring these mustangs and back them to life. Nice work!

mustang7173

 

[droptop73]

I added a 1/8" thick hardened washer to the front side of the upper when I had it apart a few weeks ago. It adds positive caster which adds directional stability. The car drives much better and has increases steering effort slightly, I like that aspect since the factory steering is way too light.