Inexpensive adjustable rear lower control arm
 

So, I'm still using stock springs on my 2013 FRS, and would like to keep doing so for the time being. I've got camber bolts and slightly slotted struts up front to get the camber I want, but the rear is still unadjustable with the stock arms.

I would really like to keep the simplicity and streetability of stamped steel arms with rubber bushings, but get some adjustability with an eccentric bushing (which is how these should've come in the first place, IMO).

I've found a very inexpensive OEM-style arm with an adjustable bushing, ULTRA-POWER's K100136. Just curious if anyone has used this particular brand/part number themselves? Kind of hard to screw up an OEM steel control arm, but figured I'd ask anyways.

SPC lower control arms are basically stock with adjustment.

Whiteline are the same as SPC, but give you an additional .5 degree of adjustment.

Never heard of the ultra-powers. SPC is the standard for OEM-style with an eccentric bolt. I've used them for 30k+ miles and quite a few track days with no issues.

I thought I'd read in a thread somewhere that the SPCs will lower the rear...is this true? That makes them a non-option for me if so..

SPC works for 99% of the folks out there that don't need bling and don't need to be compliant with autocross rules.

For the remaining 1%, it's usually because they need more adjustment or they want the bling.

SPC arms are identical to stock minus the camber adjustment + the spherical bearing.

Another vote for SPC here, mine have been holding up fine.

One other potential downside of the SPC (and I assume the whiteline) is if you are doing alignments/settings yourself without the help of a real-time display of camber and toe -- they can be hard to get dialed-in. There is some slop in the bolts/cam washers leading to a tendency to undershoot/overshoot in my experience.

That said I have about 20 track weekends using my SPC and they have held up fine.

Whoa...glad I asked. That's exactly what I want to avoid. Looks like the el-cheapos will be the pick. Can't really go wrong for $25 a piece anyways...time to use this lifetime alignment again. :)

Spherical bearing, not helm joint.

Those arms look like an exact copy of SPC/Moog/etc.

The Whitelines are the same arms with the bearing pressed out and “synthetic elastomer bushings” at the inner joint for SCCA compliance.

Spherical bearing is a normal type of joint used in automotive suspension, not some huge performance upgrade. “synthetic elastomer bushings” tend to puke out every so often and have to be maintained, in my experience.

A Heim joint is essentially a spherical bearing. Kind of like how Kleenex is facial tissue. Heim makes rod ends, standalone spherical bearings, Uniballs, etc....the word "heim" is pretty universally used when this type of bearing is referred to, especially when replacing a rubber bushing.

I've been happy with the Whiteline LCA's. They're basically the same as SPC but painted silver and the bushings are STX legal.

I’ve never heard a rubber enclosed suspension joint pressed in to an arm referred to as a “heim joint”.

Heim joint meaning an exposed metal bearing with a threaded rod. Like all the “racing” lower control arms.

Stock cars do not come with that style of joint on suspension. Lots of enclosed spherical joints on cars from the factory.

You are describing a rod end, not a "Heim joint", specifically. Rod ends are only radially rated, while spherical bearings are both radially and axially rated. Which I find even stranger, since the lower control arm is essentially a two force arm and only needs a radial rating, really. The axial load is handled by the toe arm. A rubber boot covering the joint doesn't change what type of joint it is, it just makes it a little more weather tolerant.

Or think of it another way; if you buy all your spherical rod ends from Aurora instead of Heim, what are they called then? Chances are, everyone still calls them Heims, the same way everyone points at a box of tissues and says "Hand me that box of Kleenex", even though they're made by Scott.

Yes, heim as in Kleenex, band aid, etc.

Heim joint, for your race car.

https://content.speedwaymotors.com/P...aaa7277a21.jpg

Spherical bearing (or bushing) for your 1988 Mercedes, BMW, and a million other factory fresh cars.

https://cdn.nexternal.com/vacmotors/...20e36%2046.jpg

Elastomer Whiteline bushings

https://shop.bcsauto.com/images/F221231309.jpg

Stock inner bushing.

https://www.europaparts.com/media/ca...7d0407140a.jpg




All of the stock looking LCAs with slots and cam bolts use a spherical inner bearing. The Whitelines replace that bearing with elastomer bushings for STX compliance. Heim joints (as everyone in the world refers to them as) go on race cars.

We're talking about lower control arms. They are rated to be lower control arms. Except for those $25 Chinese child labor rips offs. Those probably aren't rated for much.

Nope. That is a rod end. Possibly made by Heim, or one of a bunch of other manufacturers. Aurora doesn't sell Heim joints, they sell spherical rod ends.

It's not an escalator, it's a moving staircase!

The $25 China arm you seem to be defending has the joint you are arguing against, if that didn't come across.

My understanding is that OEM uses a plain rubber bushing/sleeve on the inboard end, not a spherical joint, and that the cheap control arm also uses rubber, which is what I want. If that's not the case, then you are correct in that this is all academic. Still, regardless of what is used at the inboard end, the $25 arm does have the eccentric bolt and washers and the tabs for them to ride against, so it's still a relative bargain for what functionality I'm looking to gain. Since no one has apparently used the Ultra-Power brand, I guess I'll be cutting edge again. lol

The OE arm uses a solid rubber bushing. The SPC/Moog/8 other brands use an enclosed spherical bushing, that is why they are illegal in STX class. The Whiteline arm is the same arm, with the spherical bushing pressed out and solid "elastomer" bushing provided.

The ultra-power arm appears to be a replica of the SPC part, spherical bushing and all. Just noticed the picture, those cam plates are going to be a bitch, flat sides on a eccentric don't work very well.

Moog/SPC/et al

https://www.fmmotorparts.com/medias/...ZmZTUxMWI1MTI2


Ultra-Power!

https://www.rockauto.com/info/782/78...36_1__ra_p.jpg

the SPC arms work fine for what you want to do and will last you a long time.

I mentioned the bearing because others have already pointed it out... it's not legal for STX classification. Whiteline will be closer to stock + adjustment with minimal possibility of play.

-alex

Welp, I took a gamble and got the MegaPowerrrzz... They do use a spherical bearing(possibly Heim branded?...lol) rather than a sleeved rubber bushing like I wanted but I couldn't find any other options, plus the price is definitely right. Installed them over the weekend and got the car aligned and was able to easily get the numbers I was looking for. We'll see how long they last; might see if I can pull the rubber boot back a bit and get some extra grease in there...

Blox LCA
 

FT86Motorsports Canadian branch have a nice deal on Blox LCA's.
And cheaper than the Whiteline units and pretty colors. Here is a link to the red ones. Not sure if their US shop offer the same pricing.

https://www.ft86motorsports.com/susp...-arms-red.html

EDIT: actually, they don't even list them on their US site. The link above is CA$. Your dollar is worth 35% more so even greater savings.

I just got a pair of coilovers for my car and found these UltraPower LCAs on RockAuto for much cheaper than the Moog’s or the SPCs, while looking fairly similar (I assume it’s a replica as others have stated).

I haven’t found much in the way of info on them other than this thread specifically; so I’d love to see how the UltraPowers been holding up for you? I don’t mind spending more for the Moog’s, however at $34CAD per arm vs $120CAD, I’d take the significant savings if the product holds up well.

They seem to be holding up as well as any other stamped steel arm would. I was able to get the alignment numbers I wanted, they installed super easy, they haven't fallen off the car...not sure what else to say?It's not a bling part, but considering i DD my car in the rust/snow belt, chassis bling is kind of pointless. It does what I wanted for short money. I'd buy 'em again.

The cheapest way to do this is with a pair of 14mm camber bolts. I have no idea why this isn't common. It's been working on my car for years now.

#Calum On the rear??????

#JBezugs I had issues with designs typical to the blox seizing and chewing out the thread. Maybe their materials have improved.

Same :iono:

downside is not a lot of adjustment. +- .5~.75 degree adjustment for $30 bux.

im learning so much:popcorn:

A two-force member is a tension/compression link only, which would be purely axial loading.
Not sure what you're saying here.

https://i.imgur.com/WARVV6N.png
https://i.imgur.com/A9XiVgV.png
....?

Funniest part is I had no idea what a heim joint was until I searched it. Upon which the results were pretty much 100% what was supplied earlier as a heim joint.

Rod end bearing.....

Or

It's a "pillow ball rose joint".

Or, because it's a big world...

A rod end bearing, also known as a heim joint (N. America) or rose joint (U.K. and elsewhere), is a mechanical articulating joint.

https://en.wikipedia.org/wiki/Rod_end_bearing

Or, squeaky noisy joints that wear out pretty quick if you dont look after them.

https://en.m.wikipedia.org/wiki/Spherical_bearing

Sticking a thread on it doesn't make it not a spherical bearing.

This argument is confusing.

A rod end is a spherical bearing, but a spherical bearing isn't necessarily a rod end. And if you refer to a rod end as a spherical bearing, you will likely confuse people and/or not get what you want.

It is kind of like asphalt concrete. Asphalt is concrete, but if you say concrete, you aren't going to end up with asphalt.

Yeah, that's not correct. Rod ends and other 'Heim' style spherical joints are radially rated, not axially.

"Dynamic Load Rating for Spherical Plain Bearings
Dynamic load rating is used for calculations when the spherical plain bearing is subjected to dynamic stress. It represents the load, constant in magnitude and direction, under which a basic rating service life, expressed as a sliding distance, will be attained for continuous oscillating movement at a defined sliding velocity and at room temperature. It presupposes that the load acting on radial and angular spherical plain bearings and on rod ends is purely radial and that the load acting on spherical plain thrust bearings is purely axial and acts centrically. "

There's a lot of people still confused about terminology, apparently. You're correct that a rod end is a spherical bearing; it simply has a male or female threaded end attached to it for ease of use.

"Rod ends consist of an eye-shaped head with integral shank forming a housing and a standard spherical plain bearing, or a spherical plain bearing inner ring, or a spherical plain bearing inner ring and a sliding layer between the bore of the head and the inner ring."

Pointing to a rod end and calling it a spherical bearing doesn't confuse anyone who works with them, other than "rod end" rolls off the tongue a bit easier.

Heim is a company who make rod ends and other types of spherical bearings. Aurora is another company who make them AST is another. They are brands, not functional descriptions. If you say "Heim", I'm going to assume you specifically mean that brand.

Precisely why I didn't want them if I could avoid it. Thankfully, these appear to be weatherproofed pretty well. And now that I said that, they're gonna start clunking... :rolleyes:

What's yer rear camber now? With camber bolts you won't have a bunch of front camber anyway, IMO just leave rear stock and balance should be fine.

Noted, thanks for your feedback! Just wanted to see if you had any issues with alignment slip or the bushings considering the price - but these seem to be a steal. Theres a few people in my group locally who have been tracking with these as well for a while and no weird issues. I just ordered a set. Can't beat it for 1/3'd of the cost of the SPC/Moog product.

Mine? I'd have to look it up again, but I'm in the ballpark of 2.6-2.7 FT, 2.2-2.4 RR, and pretty much zero toe at both ends. I'm using bolts up front, plus slotted the OEM strut body a bit to get those numbers. The aftermarket rear arms were duck soup, and the rear is much more planted now with the additional camber, without losing any of the dynamic feel I like. My tire wear is damn near perfect too.

Do you know if the rear LCA are the same in all years or did they change at some point. Rock auto doesnt list anything for 2019 but does for 2013

Yup. Just replace the inner bolt on the lower control arm.