Have the bottom rear Alta rear camber arms, but how important are the top for Daily Driving? Also what do they do and are they physically different than the bottom Alta arms?
Thanks
Mario

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For daily driving no reason to do both upper and lower. Can't speak for Alta's CAs, but when I did both upper and lower Helix CAs there was no difference.

 

You can do without adjustable upper control arms for a DD. The upper control arms control caster/toe. They should be the exact same as the lower control arms.

 

Did you notice any significant ride deterioration when replacing both upper and lower control arms?

 

Uppers are needed for toe only if you're unwilling to adjust toe via the
trailing arm mounting bolts. Uppers also let you adjust track width if desired.
There is no such thing as rear caster.

 

Just leave them alone. The lower are the most important for camber adjustability.

The only reason I would do the top arms was if I was planning on replacing all four arms with something very light weight (+spherical bearings) in an effort to drop pork from the car and tighten things up. If you're not at the race level, spend your money other places.

 

The upper control arm has a bump stop on it, and a mount for a ride height sensor for the Xenon headlights. If you replace the upper ones, then you just need to fab up a mount if you have headlights.

I have not had any issues on my car without the bumpstops, no sign of hitting the control arm on the body.

Have fun,
Mike

 

Yup

 

Who here said that they had uppers?

 

He did! ^

 

Cristo,


There is a dimension of independent rear suspension that is, essentially, caster. However, the correct term for it is "rear upright inclination". With fully adjustable race car suspension, you typically adjust the "rake" of the rear upright, just like you adjust the rake of the front upright to change the caster angle.


The reason to adjust the RUI is to minimize bumpsteer. This is done in conjunction with a bumpsteer gauge.


As with caster, it ideally should be the same, side to side, front and rear.


DOC

 

And.....if you get wheels of low offset that poke too much & hit the arches, uppers can pull them in.