# where to get control arm end? for DIY adj arms



## taverncustoms (Feb 18, 2011)

I'm not looking for the heim or polly ends. I'm trying do find the end that attaches to the hub. i belive its 2" wide ID. its the only part i cant find :banghead:


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## taverncustoms (Feb 18, 2011)

if all else fails ill just visit the local machine shop.


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## 20v master (May 7, 2009)

Custom.


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## [email protected] (May 14, 2009)

taverncustoms said:


> I'm not looking for the heim or polly ends. I'm trying do find the end that attaches to the hub. i belive its 2" wide ID. its the only part i cant find :banghead:



It will be cheaper to buy a set that are already in production. Having a machine shop do just one set of ends will cost you as much as the entire kit :thumbup:


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## Marcus_Aurelius (Mar 1, 2012)

Both ends with this platform is weird in size. None of the Universal American or Jap sizes will work, so you have to make your own. Like Noah said, by the time you're done having the yokes cold bent or machined (also need drilling and bolt welded and turned) in the proper size, thickness and material by a shop, you've almost spent the price of a set that is already made and tested.


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## taverncustoms (Feb 18, 2011)

Marcus_Aurelius said:


> Both ends with this platform is weird in size. None of the Universal American or Jap sizes will work, so you have to make your own. Like Noah said, by the time you're done having the yokes cold bent or machined (also need drilling and bolt welded and turned) in the proper size, thickness and material by a shop, you've almost spent the price of a set that is already made and tested.


mine are 2"id on the outer U that attaches to knuckle, on both my 180q and my 225Q. 2" is a standard in "Made in USA" 4 link setups and that's no JDM. The inner bushing is 2.25 on both as well. i used a micrometer. also the links that madmax uses looks like a 4 bar link. and the arms are 20.5" long from bolt center to bolt center. so a 18"-19" 4 link bar should work for the center section and if it can send a 4000lb car down a drag strip i feel safe using it on my TT.


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## taverncustoms (Feb 18, 2011)

so far 4inners and rods = 157.00 

i don't think 2" ends are gonna cost 400.00 to have made :screwy: at most 150. and thats still cheeper then the ebay control arms.


add 40.00 if i have the arms powder coated. and i get to pick color


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## Tempes_TT (Oct 24, 2010)

Dont want to be '_that guy_' but *this* is far less then $400 and much higher quality than ebay arms. 

Also, only $80 more than your '_at most_' price plus powder coat. Best bang for your buck by far. 

Only reason I brought an already made set into your specified _DIY_ thread is because you mentioned both "top of the line but too expensive" and "too cheap to care for quality" arms. Well sir, I raise you top of the line with ebay pricing.


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## warranty225cpe (Dec 3, 2008)

Tempes_TT said:


> *this*


MMX control arms FTW! Can't wait to FINALLY get my set of four! Turbo build comes first:facepalm:


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## taverncustoms (Feb 18, 2011)

Tempes_TT said:


> Dont want to be '_that guy_' but *this* is far less then $400 and much higher quality than ebay arms.
> 
> Also, only $80 more than your '_at most_' price plus powder coat. Best bang for your buck by far.
> 
> Only reason I brought an already made set into your specified _DIY_ thread is because you mentioned both "top of the line but too expensive" and "too cheap to care for quality" arms. Well sir, I raise you top of the line with ebay pricing.


i don't see why i would pay some one 80.00 to screw the ends on a 4link bar :screwy:. you make no sense sir. the only part i cant find to make your own Madmax style arm is the part that conects to the hub. i was looking to see if any one knew where to get them, or if i had to have them made. i am not saying maxmax arms are bad, in fact in copying them in a way. and i get to pick the color of the powdercoat that alone is worth it to me.

and your off on price as well 2 sets of mad max costs 270+270=540.00 I'm looking at 300.00 for all 4 at the max im hoping to have 2 sets for the price of 1 set less powder-coating.


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## Marcus_Aurelius (Mar 1, 2012)

taverncustoms said:


> i don't see why i would pay some one 80.00 to screw the ends on a 4link bar :screwy:. you make no sense sir. the only part i cant find to make your own Madmax style arm is the part that conects to the hub. i was looking to see if any one knew where to get them, or if i had to have them made. i am not saying maxmax arms are bad, in fact in copying them in a way. and i get to pick the color of the powdercoat that alone is worth it to me.


I was coming back to help you with some numbers that were a bit off and point you to things/materials that would help you in your DIY, but the tone in this post is certainly holding me back. FYI, there is more to it then screwing ends to a link. For example, a great deal of R&D went into finding the right durometer and thickness used in the MM arms. The reason for that is if you use too soft of a bushing, deflection diminishes the performance, too stiff or not enough meat on the polyurethane and NVH goes through the roof. That poly end on the MM arm is not using anything 4-link or off-the-shelf, and the proprietary custom bushing, R&D, and ultimately performance isn't simply screwing random existing parts into a tube. Same goes to the yoke end that happens to be the most critical part in terms of load and stress carried, the thickness and strength is well above anything else available for the platform or normal muscle stuff (don't believe me, I can email you comparison pictures). 

Nobody is saying you can't do it yourself and save some coin. What people are trying to tell you is that to make it to the standard set by the MM ones mentioned, you'll end up spending much more than what you said. Yes, you can have a thin section of steel bent for you using heat (which would weaken it by a good margin) and save a bit. Yes, you can have some random existing off-the-shelf bushing and housing, and use spacers (like some copycat did) to make it fit our inner bracket. It will bolt and work but does that make it proper? Unfortunately it is a question that only you can answer... and taking turns at a high rate of speed wondering if you should have built your arms better isn't exactly inspiring. I'm not saying it can't be done (I did it), however to do it with a certain attention to details is another ball game. I wish you luck and would still help you if you open yourself to understanding what many here are trying to tell you. :wave:


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## taverncustoms (Feb 18, 2011)

so far all im reading is no one knows. thanks ill just have the ends made. not gonna get into a debate about a product I also think is good VS the unknown. its pointless. thanks for the info and when i get done feel free to check out the writeup.


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## Marcus_Aurelius (Mar 1, 2012)

taverncustoms said:


> so far all im reading is no one knows.


So far your comdesceding approach is stopping you from getting help. I know and have the answer to your question... and like I said, if you can get passed that "I know it all but still asking questions" attitude I'll gladly point you in the right direction.


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## taverncustoms (Feb 18, 2011)

Marcus_Aurelius said:


> So far your comdesceding approach is stopping you from getting help. I know and have the answer to your question... and like I said, if you can get passed that "I know it all but still asking questions" attitude I'll gladly point you in the right direction.


If you know where i can get just the end that attaches to the control bar i would be very interested in hearing it if you wanna tell me why i need to buy a already made set I'm not interested sorry that's just the way I am.


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## taverncustoms (Feb 18, 2011)

20v master said:


> Custom.


lol thanks, this is the route I'm gonna go. 20v FTW :thumbup:


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## Marcus_Aurelius (Mar 1, 2012)

taverncustoms said:


> If you know where i can get just the end that attaches to the control bar i would be very interested in hearing it


Send me a PM and I'll get you to what you need!



taverncustoms said:


> if you wanna tell me why i need to buy a already made set I'm not interested sorry that's just the way I am.


Was never my intent, there is nobody more grassroots than me and I'm always encouraging DIY'ers like myself (as long as things are being done properly).


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## taverncustoms (Feb 18, 2011)

Marcus_Aurelius said:


> Send me a PM and I'll get you to what you need!
> 
> 
> 
> Was never my intent, there is nobody more grassroots than me and I'm always encouraging DIY'ers like myself (as long as things are being done properly).


cool thanks i look forward to it


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## [email protected] (May 14, 2009)

Marcus_Aurelius said:


> As long as things are being done properly.


 For safety sake


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## taverncustoms (Feb 18, 2011)

After discussing it with other members here I've decided to go with the mad max arms. saves me the time of doing it myself and i get a fully tested product. thanks.:thumbup:


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## 20v GTI Guy (Aug 20, 2001)

:thumbup:

Sent from my SGH-T999 using Tapatalk 2


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## [email protected] (May 14, 2009)

taverncustoms said:


> After discussing it with other members here I've decided to go with the mad max arms. saves me the time of doing it myself and i get a fully tested product. thanks.:thumbup:


:thumbup:


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## jbrehm (May 16, 2006)

taverncustoms said:


> After discussing it with other members here I've decided to go with the mad max arms. saves me the time of doing it myself and i get a fully tested product. thanks.:thumbup:


Good move. Max is a smart dude, and what's more, he is a stand up guy that goes way out of his way to help people - I'm sure if you ever had an issue with the arms it would be taken care of. I don't mind saying that I fab'ed up some arms, and while they worked well for a year (until the spherical bearings were shot), instead of replacing the bearings in mine, I bought some of his arms and they are a better design


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## Marcus_Aurelius (Mar 1, 2012)

taverncustoms said:


> After discussing it with other members here I've decided to go with the mad max arms. saves me the time of doing it myself and i get a fully tested product. thanks.:thumbup:


:thumbup::beer:


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## 18T_BT (Sep 15, 2005)

How do these compare to the 'mad max' ones: http://lightningmotorsports.com/i-785756.aspx or these http://forums.vwvortex.com/showthread.php?5879485-USP-Motorsports-Adjustable-Rear-Control-Arms-199


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## speed51133! (Aug 5, 2002)

mad max and gruven have versions with a poly bushing. 

thats the only REAL difference. other differences are knurling on the max ones vs machined flats on gruven to assist in turning the bars. when i put my gruven ones on i was able to turn them with minimal force using a crescent wrench to make adjustment. no idea if you really need flats or not. 

blue water performance also makes a set but in aluminum.


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## 18T_BT (Sep 15, 2005)

i'd prefer not to run poly, so the price difference is for the rubber boots on the heim joints...hmm


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## 20v master (May 7, 2009)

18T_BT said:


> i'd prefer not to run poly,


 Why not? I'm betting it's the standard Vortex poly is bad in suspension false absolute myth. :laugh:


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## Marcus_Aurelius (Mar 1, 2012)

speed51133! said:


> thats the only REAL difference. other differences are knurling on the max ones vs machined flats on gruven to assist in turning the bars. when i put my gruven ones on i was able to turn them with minimal force using a crescent wrench to make adjustment. no idea if you really need flats or not.


 I'd say that there are other differences that would classify as REAL ...but that's just me. Things like thickness/beefiness of the yokes (which happen to be the crucial component in terms of structural rigidity) for example. There's plenty more but lets stay on the ones you mentioned. 

Machining flats into a tube with .065"-.100" wall thickness (depending on the specific links available for the platform) is ground for concern IMO, especially with such a critical component. All I know is that I wouldn't trust such a practice on links in my car while flying down a sweeper at high velocity with big rubber loading the suspension... buy what do I know. 

As far easiness of adjustability, there shouldn't be any, the permanent thread coating in my mad max arms always made it a hand job for me in my car  (God only knows how many times I've made adjustments on my car with those). 

I know you had plenty to say in the past about "some dude" bashing other companies, but I can't help but keep it real. If a topic is brought up or a question is asked that sparks my interest, I'll answer honnestly... I don't know any other way. Too bad if some company didn't have their stuff together and don't like the flashlight from someone initiated in the topic. Is the mad max arms without flaws? No! I'll be the first one to say that I wish pricing (mainly due the extra effort in the name of quality and strength) was better - and that's talking as a fellow enthusiast. I also wish that the yoke could be a billet piece without welds, but again that would entails the product becoming even more exotic with pricing to match. You see, I'm not scared, and honest enough, to also put the Mad max product under the flashlight (even if that gets me banned by forum sponsors like Verdict and USRT that carries it :laugh. However, I'll be the first to say that the other options bring a laundry list of flaws that we don't even want to get into.  I usually let the community speak from their experiences, unless there is some technicalities brought into it, so I'll go back to that (and they're not "nut swinging" as it has it has been put in the past)!  :beer::beer:


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## 18T_BT (Sep 15, 2005)

20v master said:


> Why not? I'm betting it's the standard Vortex poly is bad in suspension false absolute myth. :laugh:


 
Polyurethane as a rule has no “memory” like a good rubber does. That means that weight sitting perpendicular from the axis of the bushing WILL deform and will stay that way. It does NOT return to it’s original state after deformation. You can check this yourself by installing an LCA bushing for example and don’t drive it. Jack it up a week later and you will be able to move the inner sleeve by hand. Add a few thousand miles to that and it’s toast. I have run (not all on my mkiv) poly, hard rubber, delrin, and full spherical. This is my take on it: 


Polyurethane: Good for any bushing that simply turns and does not support the weight of the car, or the weight of any corners roll moment. It is arguably OK for mounting a motor or our stock dogbone with inserts (good example is VF mounts - oh where do I begin with them, the dogbone middle round poly always breaks on people and hence why most don't replace it on the stock dogbone where most leave it as rubber, and eventually the tranny/engine mounts mushroom, why do you think Ed makes Delrin and now metal inserts) where the primary weight is handled by a metal sleeve like in Hondas and the bushing is a vibration aid only like the dogbone inserts on our cars. It’s total lack of return to shape after deformation is the sole reason to punt on this garbage, who cares if it is Teflon impregnated or not like powerflex. When I used this material, they have to be replaced every single year, since I don’t put loads of miles on my car, it was from sitting with weight on it that caused to deform. Even shift linkage bushing deform after a year of use why do you think Ed and others use stainless or even bronze alloy like Mike P. 


Rubber/Hard Rubber: Assuming a non-absurd durometer, this is hands down THE BEST option for light track, autocross and especially street driving. Rubber can “cycle” endlessly, one of the reasons it's OEM top choice for this material that can outlast the car in some cases. Its predictable for the most part, but it’s downfall is it’s compliance. For independent suspension where things aren’t always moving in a single axis, they can move under load inducing hysteresis in your suspension motion, which can be a handling nightmare at it’s extremes and lead to binding or whatever depending on design. 


Spherical: Best option for whatever you throw at it, but COST and DURABILITY are a serious concern. IMO, never use them for street driving, even with very good bearings and covers for them. They are a consumable at this point, now that you are working with metal-to-metal contact. Spherical bearings vary immensely in terms of precision and metal grades, as well as cost. For example, a motorsports grade rod-end might run you 20 bucks, but a high-end PTFE lined might be double that…PER PIVOT! On the plus side: they completely remove hysteresis, and force the suspension to move in single axes like it was designed to do. They do introduce more/different stresses to things, and other weaker links may be exposed. They are seriously noisy, subject to corrosion, and need to be checked for looseness often. Much like Marcus said in another thread, most people don't know how to check to make sure they are worn. The more you spend on them, the longer they last, but they are still consumable and pricey as hell. When you add R-compound and high lateral-G forces to the mix, these are the way to go to avoid binding in extreme situations. 


This is just my experience, over the years I have learned quite a bit about making a FWD pile work for me but came to this forum because I am getting a TT and wanted to learn more about AWD platforms…certainly not the last word by any means, but it is also far from internet/kotex hearsay.


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## Marcus_Aurelius (Mar 1, 2012)

18T_BT said:


> i'd prefer not to run poly, so the price difference is for the rubber boots on the heim joints...hmm


 Since you're set on Heims, nothing wrong with that if it's the kind of application you have for the car (full track that won't compromise even virtually unnoticeable deflection from properly chosen poly... even if that means NVH on normal roads and increased cost of servicing and replacements). I would probably go with the United ones over the other China special that you linked (those are seriously scary). And to be honest, CPT would be the Heim-jointed one I'd pick first, then Gruven (not the ones you posted). 



20v master said:


> Why not? I'm betting it's the standard Vortex poly is bad in suspension false absolute myth. :laugh:


 What are talking about MR engineer? 24 Hour of Lemans teams, multiple engineers, all kind testing capacity, and nearly unlimited budget choose to run poly in their critical suspension links just for the hell of it... Or is it because they don't want to gamble such an effort with components with low lifespan and high potential for failure in extended use? I'm sure the Vortex myth-makers know better than those teams! opcorn:


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## 20v master (May 7, 2009)

18T_BT said:


> Polyurethane as a rule has no “memory” like a good rubber does. That means that weight sitting perpendicular from the axis of the bushing WILL deform and will stay that way. It does NOT return to it’s original state after deformation. You can check this yourself by installing an LCA bushing for example and don’t drive it. Jack it up a week later and you will be able to move the inner sleeve by hand. Add a few thousand miles to that and it’s toast. I have run (not all on my mkiv) poly, hard rubber, delrin, and full spherical. This is my take on it:
> 
> 
> Polyurethane: Good for any bushing that simply turns and does not support the weight of the car, or the weight of any corners roll moment.
> ...


 I've heard all these stories like yours about poly in control arms, yet the poly I've used in my Mk4 arms since less than 10K miles all the way to 240K miles after I quit driving it look just like new. No wear from the grease attracting grit/sand/dirt, no deformation, no signs of binding/cracking, nothing. Yet everyone swears they don't last, deform, and bind. That hasn't been my experience. 

Your description of poly and when it's good is exactly what they are doing in arms like Max makes. 

Lastly, it's exactly that: hearsay. See Max's reply above this for more info.


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## 18T_BT (Sep 15, 2005)

Marcus_Aurelius said:


> What are talking about MR engineer? 24 Hour of Lemans teams, multiple engineers, all kind testing capacity, and nearly unlimited budget choose to run poly in their critical suspension links just for the hell of it... Or is it because they don't want to gamble such an effort with components with low lifespan and high potential for failure in extended use? I'm sure the Vortex myth-makers know better than those teams! opcorn:


 
I would venture to say it's because they are replaced extremely often. 


Adam - look up the definition of hearsay, I am basing it on my experience not yours :thumbup:


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## 20v master (May 7, 2009)

18T_BT said:


> I would venture to say it's because they are replaced extremely often.
> 
> 
> Adam - look up the definition of hearsay, I am basing it on my experience not yours :thumbup:


 No, if that was the case they'd just use spherical/heim/rose joints in everything. So if it's your experience, what happened that made you conclude poly is bad?


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## Marcus_Aurelius (Mar 1, 2012)

On top of that let's not forget that we're discussing lateral links on the multi-link rear that has the trailing arm supporting all the weight and vertical loads. Some valid points are put forth about how poly behave compared to heims and rubber, but the bulk of it don't apply to the location in question. Lateral loads, which is what the lateral links are in charge of controlling dynamically, are braced axially by the trailing arms. So, unless you have defective trailing arm mounts, this is negligible. That leaves us with radial loads: 

1) the rear link bushings don't see any of that at rest. So, the memory/deformation property don't apply in this location 

2) dynamically, the loads are there but constantly rotating around a short lever (distance from center axis to outer most point of the bushing) and not capable of keeping loads centric to a specific point on the bushing. 

3) since we're at it the potential performance from metal to poly can be negated if the durometer is carefully picked (it is on some and not so much on others arms). If the durometer is chosen to take and exceed the load exerted by the short leverage placed on them there will be no discernable performance loss or deflection.


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## PLAYED TT (Oct 17, 2010)

Marcus_Aurelius said:


> What are talking about MR engineer? 24 Hour of Lemans teams, multiple engineers, all kind testing capacity, and nearly unlimited budget choose to run poly in their critical suspension links just for the hell of it... Or is it because they don't want to gamble such an effort with components with low lifespan and high potential for failure in extended use? I'm sure the Vortex myth-makers know better than those teams! opcorn:


 Speaking of gambling I wonder if you gruven arms will finally snap so I can get some new ones that wont corrode and rust to pieces. :laugh:


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## Marcus_Aurelius (Mar 1, 2012)

PLAYED TT said:


> Speaking of gambling I wonder if you gruven arms will finally snap so I can get some new ones that wont corrode and rust to pieces. :laugh:


 I don't think you really want that to happen James, especially at speed in a turn... or in your case, leaving a show or a meet's parking lot with all the bags guy to come and say "I told you so, bagz or bust".  

The old versions with the nut welded around the tube, and welded inserts at both ends (which I believe you have) weren't put together as well as the newer stuff - which happen when they finally accepted/realized that improvement was possible (or was it competition). :laugh:


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## PLAYED TT (Oct 17, 2010)

Marcus_Aurelius said:


> I don't think you really want that to happen James, especially at speed in a turn... or in your case, leaving a show or a meet's parking lot with all the bags guy to come and say "I told you so, bagz or bust".
> 
> The old versions with the nut welded around the tube, and welded inserts at both ends (which I believe you have) weren't put together as well as the newer stuff - which happen when they finally accepted/realized that improvement was possible (or was it competition). :laugh:


 Oh I know I don't want it to happen but it's bound to happen sooner or later. I know they should be ok as they aren't seized and I grease them regularly. The biggest test will be when i get my alignment after putting the car back together. Since they were only messed with when put in new and never adjusted since. Hey $600 for a solid 2-3 years of lifespan seems like a steal right:sly:


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## 18T_BT (Sep 15, 2005)

On top of that let's not forget that we're discussing lateral links on the multi-link rear that has the trailing arm supporting all the weight and vertical loads. Some valid points are put forth about how poly behave compared to heims and rubber, but the bulk of it don't apply to the location in question. Lateral loads, which is what the lateral links are in charge of controlling dynamically, are braced axially by the trailing arms. So, unless you have defective trailing arm mounts, this is negligible. That leaves us with radial loads: 

_Like I said in my original post, most of my experience is in FWD control arms so that's what I am basing it off. Why do most companies use rubber/spherical for rear control arms? Even the EVO/WRX control arms._ 

1) the rear link bushings don't see any of that at rest. So, the memory/deformation property don't apply in this location 

_Maybe not, but the rear link bushings in real world applications where pot holes exist, poly should have this exact problem. Again, spherical allows for full articulation without any slop and rubber allows for full articulation with some slop. Poly limits slop by preventing proper articulation. Essentially just smashing against it until it wears out. _ 

2) dynamically, the loads are there but constantly rotating around a short lever (distance from center axis to outer most point of the bushing) and not capable of keeping loads centric to a specific point on the bushing. 

3) since we're at it the potential performance from metal to poly can be negated if the durometer is carefully picked (it is on some and not so much on others arms). If the durometer is chosen to take and exceed the load exerted by the short leverage placed on them there will be no discernable performance loss or deflection. 



What are these race teams and where are they using poly? I still think that poly does not go in any rotational application.


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## 20v master (May 7, 2009)

18T_BT said:


> On top of that let's not forget that we're discussing lateral links on the multi-link rear that has the trailing arm supporting all the weight and vertical loads. Some valid points are put forth about how poly behave compared to heims and rubber, but the bulk of it don't apply to the location in question. Lateral loads, which is what the lateral links are in charge of controlling dynamically, are braced axially by the trailing arms. So, unless you have defective trailing arm mounts, this is negligible. That leaves us with radial loads:
> 
> _Like I said in my original post, most of my experience is in FWD control arms so that's what I am basing it off. Why do most companies use rubber/spherical for rear control arms? Even the EVO/WRX control arms._
> 
> ...


 Roatation in one axis = fine. In multiple, like the rear of our front arms = not the best. If you don't believe us, get sphericals and check them often. I've been using Max's arms for over a year with out any if the problems you keep insisting will happen. You ignored my last question about your actual negative experiences conveniently though.


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## 18T_BT (Sep 15, 2005)

Like I mentioned about the VF mounts. I also had the oval in my control arms. Sorry I didn't take picts.


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## 20v master (May 7, 2009)

18T_BT said:


> Like I mentioned about the VF mounts. I also had the oval in my control arms. Sorry I didn't take picts.


 The VF dogbone inserts fail because there are two points of rotation that are fixed together (this places extreme side loads on the inserts), and it has to do with extreme pulse cycling (due to rpms of the engine) relative to what the suspension sees. It's also a very thin insert/bushing, which doesn't help. It's a poor design overall and poor application for poly. You had the oval in the front or rear of your control arm? I'm going to wager you had poly in both but only oval'ing in the rear, because that's also two axes of rotation. Again, neither of these is comparable to the application of using poly on the inner joint of the rear lateral link (as Max and I laugh about, it's not even a control arm at all).


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## Marcus_Aurelius (Mar 1, 2012)

18T_BT said:


> 1) _Like I said in my original post, most of my experience is in FWD control arms so that's what I am basing it off. Why do most companies use rubber/spherical for rear control arms? Even the EVO/WRX control arms._
> 
> 
> 2) _Maybe not, but the rear link bushings in real world applications where pot holes exist, poly should have this exact problem. Again, spherical allows for full articulation without any slop and rubber allows for full articulation with some slop. Poly limits slop by preventing proper articulation. Essentially just smashing against it until it wears out. _
> ...


 
1) Most car manufacturers use rubber in the locations where spherical bearings aren't suitable. Reason for that is mostly cost, not because using a polyurethane would be bad or not effective. EVO and WRX are still mass produced vehicles that haven't been built to be a blank canvas for rally in long time (they haven't been designed with homologation in mind in over a decade). 

2) Again, you're negating the fact that just like rubber, polyurethane comes in various grade and durometer. They have to be chosen to match the location they will be used, and just like rubber, get them in the wrong grade or durometer, and they will wear out quickly. Do your homework and pick the correct grade poly, and they will last just as long as if they were used in locations that aren't subject to rotation (off the shelf poly won't cut it there). What you seem to not grasp when you say "poly limit slop by preventing proper articulation" is that in the specific location in question, there is not much "articulation" in play (which would require deflection of rubbers or poly). Two planes are in effect dynamically, as I explained before, and the trailing arms blocks/restricts any longitudinal articulation (axial deflection). Whatever transverse articulation (radial deflection from the suspension traveling up and down dynamically) should be no problem for a proper poly to handle (as long as there is no problem with the rotation of the bolt inside of the sleeve in the link, creating some binding). 

3) I don't want to argue your convictions, they must be based on something. However, the fact remains that you have a couple hundreds of examples in this very forum (including myself with the abuse that I put the platform through with huge race slicks) as a testimony that proper proprietary poly with R&D behind them works at that location in the TT/R32 for extended time and all conditions (at least a lot longer than Heims could ever dream). If it make you feel good, I can make you or any anyone some Heim-jointed arms, but why would anyone want to do that if you don't get any discernable performance and reduced life out of it. I am not trying to sway your selection (far from it) but we are telling you this because we know a bit on the subject and the dynamics involved. (The R32 road racing contengency all swear by the poly solution after they had to replace Heims constantly for years - Tempes_TT in this board got into a rear accident that damaged his rear wheel pretty badly, the poly arm was unphased and still in his car and going strong). 

As far as providing proof that endurance teams are choosing poly in various suspension locations, that for you to research (guess where I got my contact to get the custom poly used in our rear links made)


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