Adjustable Upper Control Arm
 

I'd like to add some additional camber adjustment in the rear of my car, but it doesn't look like there are a lot of options available. I see FM and V8Roadsters offer them at up toward $300. I was just curious if there are any other options out there I may have overlooked?

There's no way to add an eccentric bolt to the stock control arms is there? Sure would be nice to figure out an effective $20 fix.

You could do something like AWR does.

Control Arm - Rear Upper Adjustable Bare - AWR Racing Store

ISC sells offset bushings for the rear upper control arm: Suspension | ISC RACING SERVICES Note that these are made from delrin, which is extremely hard, and thus there will be a bit of a NVH penalty.

SuperPro manufactures a set of bushings with offset centers for the rear lower, which are polyurethane, so stiffer than OEM rubber, but not solid like delrin: SuperPro Bushing Kit for MAZDA MX-5 NA - 1990-1998 These are available from various distributors, such as Trackdog: http://trackdogracing.com/superpro-adjkit-rear.aspx


There also this set of adjustable rear upper arms which are $245 a pair: http://store.awrracing.com/control-a...justable-bare/ (It's a stock upper arm with the end cut off and an eccentric bolt retainer welded on. The benefit here is that if you wish to, you can use OEM rubber bushings.)

Awesome links Joe, thank you so much. I knew something had to exist, just wasn't sure where to look or what I was looking for.

The last link I posted it actually the exact thing you were asking about vis a vis "There's no way to add an eccentric bolt to the stock control arms is there?" If you're sufficiently confident in your welding skills to hack up your control arms, you could replicate this at home.

Cut ours in half. Welded end plates and nuts. Used 5/8" rod between with lock nuts. About $20, but a fair amount of work.

I would rather see this method executed with shims and two through bolts (I don't remember if the sheet metal arm is open on one side to make this possible). But, threads in bending = bad.

Agreed. You see this sort of design in upper rear arms sold on eBay, as well as those made by such amazingly talented shops as Megan Racing, which makes me want to avoid it.

Another low-budget option exists for the person skilled with a welder. If all you want to do is change the range through which the lower eccentric bolts are capable of moving the wheel in static camber (and assuming you with to make static camber more negative, not less), you can just cut a slice out of the midshaft section of the upper arm with a chop saw and then weld the two pieces back together, effectively shortening the arm by a small amount. This is effectively what the ISC offset upper bushings do.

4 years. 2 of those on 10" Hoosier slicks and 2 of those on 12" Hoosier slicks. Zero issues. Can't argue with what works.

Sure there is. Is been on my long list of things to R and D. Slot the hole like the LCAs have and weld on a u shaped retainer thing for the cam to sit it. done.


Also, offset delrin bushings.


edit- im way late, lol