Are the rear trailing control arms on the GP already aluminum and already adjustable? If adjustable, are they as adjustable as the top aftermarket ones?

 

Control arms or trailing arms?

 

upper and lower have no adj in them. You have a bolt with min. adj in it. Get the Alta arms if you track your car a lot. You will get noise with heim joints though. If you don't want any noise look at the Ireland arms. I have the Alta's and like them. Some noise but they work on the track.

 

Hopefully somewhere I can find a definition with pics to help me understand the difference between rear control arms and rear trailing arms!

What arrived today (that I ordered and then "all of the sudden" asked myself whether I ordered what the two shops told me to get) are adjustable lower control arms (based on what the sheet of paper in the box says ... although it also says "MINI Cooper rear camber arm" at the top of he sheet, too).

When I go to my GP in the garage and look underneath, it seems like they will take the place of the bottom-most "arms" and will replace a non-adjustable piece with ability to adjust.
This is what I ordered:

www.promini.com/product-exec/product_id/4164/search_year/2006/search_model/100

And here is the description of the product from the website:

"Billet Aluminum Rear Trailing Arms - The O.E. factory rear trailing arms are constructed of stamped mild steel. This is MINI's choice to keep the vehicles production cost within target selling price. Although this type of construction may be satisfactory for street driving, it is not a good choice for track applications. These new billet aluminum rear control arms are much stronger and have the added feature of additional camber adjustment. Changing camber is important to allow for proper wheel alignment. This is a must for track applications where lowering the vehicle beyond factory specs will require additional adjustment range that is unique to this product. The center turn buckle adjuster allows for easy track side adjustment. Kit includes both left and right rear control arms."

 

WELL that can make it confusing. The trailing arm is generally referring to the arm that extends from the forward sub frame back to the wheel. The control arm (sounds like that is what you have in the box) extends from that point out at the wheel back toward the subframe. True the GP has some adjustment already built into the rear control arms (as do all 05+ models) but the arms you purchased will help with rear tracking, more camber adjustment etc.

newbs49: Thanks for the plug! Chat soon!

 

Thanks and now I understand. I went to the GP in the garage and can visualize it properly now. In this instance, I just want the lower control arms, correct? Also, I notice the lower control arm (stock on the GP) is aluminum, whereas the upper control arm looks like stamped mild steel. Are the upper and lower control arms (in stock setting) normally the same length? Is there any benefit to moving the (stock) aluminum lower ones up top (replacing the stock steel ones)? Is there any benefit (and if so, is it worthwhile) to doing adjustable upper control arms?

 

Rear control arms-

There are upper and lower arms for each rear wheel.

Most of the time we upgrade only the lower rear control arm so we can adjust rear camber (to a larger extent).

Example of Alta V2 lower rear control arms-


Or Helix adjustable rear lower control arms-


Most of us leave the upper rear control arms alone. You can replace them and if they are adjustable for length then you can make some adjustments that will affect alignment. Since the lower control arms are all that are needed to make adjustments to rear camber then that is all we upgrade, partly to save money.

Certainly the upgraded control arms look nicer and in some cases weigh less than the stamped steel control arms you mentioned. Upper and lower control arms appear to be about the same length and not adjustable (the stock stamped ones). Upgraded ones can be made to be the same length as the stock ones and then alignment can be adjusted from there. It is possible to more the lower alloy control arms to the upper positions and upgrade the lowers to adjustable control arms. You might want to confirm this with one of the vendors that does installs for lower control arms. Be sure to mention your year and model of MINI.

 

if i change the upper contorl arm ,is that mean's i can adjust the toe on the upper arm right?

 

Correct.

You don't need to upgrade the upper rear control arm. You can adjust rear toe without doing that.

But if you do upgrade the control arm and put in and adjustable arm then you can adjust toe in the rear.

 

My GP has M7 coilovers, H-sport rear comp sway bar, H-sport adjustable camber plates, H-sport adjustable lower control arms. Handles beautifully.
Here's some pic's showing the stock and H-sport lower arms

 

I want to adjust my rear camber more than the stock GP eccentric bolt allows, but all of these control arms have exposed heim joints. My understanding is that heim joints don't hold up to street use, especially in the northeast where we put salty sand on the roads all winter.

The Alta Vista web page says: " All these features add up to a part with both performance benifits, and durability that lasts forever."

Is it the nylon impregnation that keeps the joints from sanding themselves to death? Several of my BMW friends bought adjustable rear control arms with heim joints from turner and all of them had to be replaced after a single winter.

thanks for any info

-john

 

This is also a good explanitory shot for the OP.

Lower Control Arm: Often shortened to "LCA" - the aftermarket H-sport part.

Trailing arm: the aluminum part the wheel and shock attach to. This is the part that is different on the GP than on other R53 models.

 

If replacing the lower control arms with something more adjustable (such as the H-Sport arms), can the stock lower control arms be moved to the top control arm location to obtain easier toe adjustability. If so, is there enough adjustability for adjusting the toe (something like +/- 1/8")?

The reason I asked is on my 2003 MCS, that I had installed adjustable lower control arms, the alignment shop would not adjust the rear toe by loosening the trailing arm bolts because his data said a special BMW tool was required. I told the shop that it could be done by a little trial and error but they would not adjust the rear toe.

I figure it would be much easier to get a shop (or myself) to adjust rear toe if the top control arm is adjustable.

 

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What adorable machine , the engine is exquisite
! We love machines!