What are control arms?

[janus77]

Just out of interest, what are the M3 control arms, would they give any improvement in handling on their own over stock?
Just interested to know a bit about them..

Cheers

[Lester]

Control armFrom Wikipedia, the free encyclopediaJump to: navigation, search

Double Wishbone SuspensionIn automotive suspension, a car wishbone is a nearly flat and roughly triangular member (or sub-frame), that pivots in two places. The broad end of the triangle attaches at the frame and pivots on a bushing. The narrow end attaches to the steering knuckle and pivots on a ball joint.

Two such devices per wheel make up double wishbone suspension, while one control arm per wheel makes up a part, usually the lower part, of MacPherson strut suspension or of various other configurations.

[edit] ReferencesCar suspension at Howstuffworks.com

[janus77]

thanks, had wiki'd it already, not sure how the M3 control arm is superior to the regular 1'er, and what benefits it might give..

[MikeVictor]

Originally Posted by janus77

Just out of interest, what are the M3 control arms, would they give any improvement in handling on their own over stock?

The short answer is yes.

Originally Posted by janus77

Just interested to know a bit about them..

The M3 wishbone and tension struts will change the handling of your car in (what's generally considered) a good way, by improving steering feedback to the driver and handling through the different design of the units and the introduction of increased negative camber. I've read the E9x control arms introduce camber at about -0.75, if you want more you'd likely need camber plates.

If you can, try to find someone in Sydney who's car specs are close to yours with the modification done, and see if the owner will let you try it out to feel the difference.

If you're tracking your car at a Club level from time to time, it's a good mod for the money. Sway bars are also worth looking into and if you're feeling like treating yourself get some springs and shocks done too

Hope this helped mate.

[janus77]

Cheers, yes thanks, so basically they'll increase the neg camber, giving you better traction in the corners, but potentially a little more squiggly on the straights, and may increase tyre wear a little?
I've got sways, but wondered if it might tighten up how quickly the car settles after changes in direction, however probably that's the point where coil overs are needed.

[Jeef Beef]

The most significant change would be to just get coilovers. Things like sway bars, control arms and strut braces can be changed after that to give marginal gains.

IIRC on stock everything you can give a max of -2 degree camber just with wheel alignment, more than that camber plates are required.

[madmaxhk]

Originally Posted by Jeef Beef

The most significant change would be to just get coilovers. Things like sway bars, control arms and strut braces can be changed after that to give marginal gains.

IIRC on stock everything you can give a max of -2 degree camber just with wheel alignment, more than that camber plates are required.

Coilover and sway bar will give you firmer ride, less body roll, better control of car, but Only M3 control arm will give you sharper, better and more precise steering feel. Due to the M3 control arm has stiffer bushing than the stock one.
I highly recommend you get the M3 wishbone together with the control arm.

[bogart]

everyone is missing this part... they 'control' the suspension/wheel movement in an up and down direction, and keep the geometry in check.

the M3 control arms are slightly longer, pushing the bottoms of the wheels out, thus giving you -0.75 deg camber.

[Focusedintntions]

They also have stiffer bushing so you have less deflection under hard cornering which helps the steering geometry remain more accurate and planted. Also helps with the feedback you get in the steering wheel.

[Biasasaja]

all i can say is they are freaking awesome, ive had them installed a couple of days ago in my car and its just soooo sweet to corner, feels liek a proper m car (also had quaife installed)

[e82n54]

Where can I purchase M3 control arms? Dealer?

Are M3 control arms recommended for both front and rear or front only?

I found this, but it's aftermarket and for the rears only.

http://www.**********s.com/Rogue-Engineering-E9X-M3-Rear-Control-Arms.htm

[Kamal]

Originally Posted by Scuderia000

Where can I purchase M3 control arms? Dealer?

Are M3 control arms recommended for both front and rear or front only?

I found this, but it's aftermarket and for the rears only.

http://www.**********s.com/Rogue-Eng...ntrol-Arms.htm

Dealer is an option but I'd go through the parts departments of Dan@UnitedBMW or Tischer BMW... also, Harold@HPAutowerks is our forums goto suspension guy, I haven't dealt with him personally, but I think ALOT of people would highly recommend him. I think Turner Motorsports also carries the parts... but as far as I know, they don't sponsor the forums.

[Focusedintntions]

I got mine from HPA...they have the best prices on the fronts for sure.

[Xaeryan]

Originally Posted by Focusedintntions

I got mine from HPA...they have the best prices on the fronts for sure.

Harold seems like a great guy and he's very involved with our community. You'd have technical support if you needed it. But HPA doesn't have the best prices on the fronts (or rears for that matter). It also appears that he is back-ordered on them from his website, although it might be worth giving him a call to check status/price. Dan @ United is also great, heavily involved here, and I have personally had great support from him. Tischer seems like the least involved with the community (don't get me wrong here - they're still pretty involved and Evan posts when needed), although they generally have the best prices from my research. Buy from any of these three and you're supporting the enthusiast community.

[GaryS]

Originally Posted by Scuderia000

Where can I purchase M3 control arms? Dealer?

Are M3 control arms recommended for both front and rear or front only?

All the M3 suspension parts are recommended, but afaik everyone says the front control arms and rear subframe bushings are the best bang for your buck.

[Focusedintntions]

Originally Posted by Xaeryan

Harold seems like a great guy and he's very involved with our community. You'd have technical support if you needed it. But HPA doesn't have the best prices on the fronts (or rears for that matter). It also appears that he is back-ordered on them from his website, although it might be worth giving him a call to check status/price. Dan @ United is also great, heavily involved here, and I have personally had great support from him. Tischer seems like the least involved with the community (don't get me wrong here - they're still pretty involved and Evan posts when needed), although they generally have the best prices from my research.

I talked to Dan at united just this past week...said he couldn't match HPA's prices for the full front set...

[Xaeryan]

Originally Posted by Focusedintntions

I talked to Dan at united just this past week...said he couldn't match HPA's prices for the full front set...

So that leaves one more to check that I listed.

[Oofie]

How difficult is the install for the M3 control arms?

[Kcc]

Lets steal this thread for a bit...

Been searching for a while, but still didn't find the exact answer. Are control arms, wishbone and tension rod 3 different thing?

Changing 135i OE control arms bushing will not give you the -0.75 camber? Or am I messing up my info?

What does the tension rods do?

Thanks!

Kcc

[Focusedintntions]

If i'm not mistaken I believe a tension rod can be another name for a sway bar...

Depending on the kind of suspension setup you could have control arms and wishbones or one or the other. They're all different parts and generally are not interchangeable with each other.

[Xaeryan]

Originally Posted by Oofie

How difficult is the install for the M3 control arms?

Not hard for the fronts - one (big) nut per arm/rod at the hub carrier, one (big) bolt per arm/rod at the front sub-frame. Can be accessed with the wheel off; tension rod is easiest with the under-tray off as well. The primary issue I ran into was the lower control arm fit was very snug at the sub-frame, and required a bit of cleaning up with an emery cloth/light file at the sub-frame before I could stuff it into place. It'll become apparent what I mean if you run into the same issue; easily resolved. The tension rod went in smooth though.
The other issue I recall is that the washers on the nuts are special lock washers with raised tabs (for a lack of a better description) that cannot spin. The tabs fold over the nut to also prevent it from spinning. The tabs are easy to break - I ended up breaking mine, but I'm not worried since I followed torque specs and rechecked it after a bit of usage.

EDIT: You will need an alignment after installing the control arms, as it throws the toe way off (in).

[GaryS]

Originally Posted by Kcc

Lets steal this thread for a bit...

Been searching for a while, but still didn't find the exact answer. Are control arms, wishbone and tension rod 3 different thing?

Changing 135i OE control arms bushing will not give you the -0.75 camber? Or am I messing up my info?

What does the tension rods do?

Thanks!

Kcc

The upper arm is also called tension rod. The lower arm is sometimes called lower wishbone. Both arms together = front control arms.

The lower arm, or wishbone, is the one that adds camber; it also adds firmness and feel. The upper arm adds a lot of firmness and feel.

The Dinan High Performance Bushings kit that started all this includes the M3 upper front arms and M3 rear subframe bushings. http://www.dinancars.com/shop/D280-0...shing-Kit.aspx

edit: I see the Dinan ad says "front lower control arms". Well, what do I know? I had this stuff installed by a shop and am just repeating what I've read. Maybe someone else can correct if I got that wrong.

If you replace the bushings that are in the stock wishbones, you will add firmness and feel but not camber.

Upper: http://www.hpashop.com/product.sc?pr...categoryId=237

Lower: http://www.hpashop.com/product.sc?pr...categoryId=237

Both: http://www.hpashop.com/product.sc?pr...categoryId=237f