Upper Control arms

[Dreamcar]

Simple question: Is it worth it to get adjustable upper control arms? I'm not building an autocrosser, but I may go with 17 or 18 wheels.

[Mike DC]

      
I dunno if you will get anything out of something with a lot of adjustment range.  

But most non-adjustable aftermarket UCAs are designed to add 3-4 degrees of caster into the alignment compared to stock, and that is worthwhile.

 

[Dreamcar]

What makes it worthwhile?

[HPP]

The stock control arms can maybe only get 2-3* worth of positive caster. Putting offset bushings in them may get you 4-6* of positive caster. Most aftermarket tubular arms provide up to 8-10* worth of positive caster.

FWIW, the stock alignment specs are roughly -1 to +1 degrees of caster, depending on manual vs power systems. By increasing caster beyond the spec, you increases the car's higher speed stability, the steering's return to center ability, it increases dynamic camber when turning, and it also increases steering effort, which will help overcome some of the Mopar over-assist.

With those benefits, are the aftermarket arms worthwhile, it depends. The stock arms with $30 worth of bushings will get you most of the way there. Are the aftermarket arms worth $300 for an extra 5* of caster, it depends on how hard you're going to be driving it.

[Dreamcar]

The stock control arms can maybe only get 2-3* worth of positive caster. Putting offset bushings in them may get you 4-6* of positive caster. Most aftermarket tubular arms provide up to 8-10* worth of positive caster.

FWIW, the stock alignment specs are roughly -1 to +1 degrees of caster, depending on manual vs power systems. By increasing caster beyond the spec, you increases the car's higher speed stability, the steering's return to center ability, it increases dynamic camber when turning, and it also increases steering effort, which will help overcome some of the Mopar over-assist.

With those benefits, are the aftermarket arms worthwhile, it depends. The stock arms with $30 worth of bushings will get you most of the way there. Are the aftermarket arms worth $300 for an extra 5* of caster, it depends on how hard you're going to be driving it.

Thank you. Its a cruiser, so I'll probably just get the bushings.

[SovereignZuul]

In doing my research very recently and talking on these boards about suspension stuff I'd say it's worth it depending on budget.

I won't build my car without such an upgrade!

Check out this article.
http://www.hotrod.com/techarticles/chassis/hrdp_0909_mopar_suspension_bolt_ons/

People have explained to me that the upper arms that relocate the ball joint give significant improvements to high speed (highway) stability and remove the weird floaty-ness that these cars can get.

Don't budget by Hotchkis' website prices, the parts can be had much cheaper through someone like Summit.

[HPP]

Thank you. Its a cruiser, so I'll probably just get the bushings.

You bet. its worth noting when you do this, the bushings must be installed the opposite way of what the instructions say. This is because the bushings were designed to provide additional camber and you are going to be getting extra caster out of them instead.

Once installed,  you also want modified alignment specs to see benefits from using them. assuming you are using radials, you will want to go with 3 to 5* of positive caster, 0 to neg .5* camber, and .125" total toe. Easy way to remember is to ask for the alignment for a 2000 Mustang. This also allows a new(er) alignment tech to punch in a car their system recognizes.

[Dreamcar]

Thanks guys!!

[Mike DC]

Easy way to remember is to ask for the alignment for a 2000 Mustang. This also allows a new(er) alignment tech to punch in a car their system recognizes.

Nice.  I'll have to keep track of that one.