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Spherical Bearings in Stock arms

I see a lot of ppl buying aftermarket arms, of course many want the adjustability however if you dont lower the car stupidly and dont need a fix roll centres etc I was wondering why dont more people take their strong and F*&K stock control arms, toe arms etc to a bearing place and get the rubber replaced with a solid bushing. 

Thinking of giving this a crack. Any thoughts or issues with this or has anyone got experience with doing it?

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Having bent standard lower control arms and brackets in the front end if a R33, "strong as f**k" is probably not the word I would describe standard control arms. Not that I would recommend super strong control arms... I'd rather the arm bend or break in an accident rather than the mounting points on the body of the car.

The main issue I see with the idea of spherical bearings in standard arms is that the kind of person that wants to eliminate all potential slop in the suspension at the cost of NVH is also the kind of person that wants camber adjustment, which standard control arms simply provide hardly any in the rear end and absolutely none in the front. Not everyone uses adjustable for camber correction after "slamming" their car, some of us want -3 degrees for track days ;)

Here's the thing.  Of all the parts of an aftermarket suspension arm, the ONLY part that is not road legal is the spherical bearing.



My interpretation of the rules makes me think that you just need to get an engineer to sign off on it

https://www.google.com.au/url?sa=t&source=web&rct=j&url=https://infrastructure.gov.au/roads/vehicle_regulation/bulletin/pdf/NCOP11_Section_LS_Tyres_Suspension_Steering_Nov_2015_v4.pdf&ved=0ahUKEwiwwNSJ6ZXPAhWEmZQKHQn5C_EQFgggMAI&usg=AFQjCNFZ6jheyXhqRGWl3zaZ7qbZSGK2hg&sig2=vBG4FoqZkRegERGwLHFkqQ

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Spherical bearings deal with arm-mount gross misalignment issues when altering ride height and alignment.

Otherwise stick with rubber.  Far more durable than uniballs on the road, and won't flog out like urethane.

Too many people zero-in on the idea of "removing slop", when their changes have fundamentally shifted the alignment away from "right".  Adjustable length arms are far more important to making the car handle and feel right once moving away from stock.

  • Like 1
15 hours ago, Cassbo said:


My interpretation of the rules makes me think that you just need to get an engineer to sign off on it

 

 

 

Talk to an engineer Matt, and see how they interpret that.  Perhaps they will.

Quick count I think there's at least 16 pivots/mounts that could go to uniball in an R chassis.  At ~ $100 per joint for quality replacement (no sane person would install low quality sphericals - would they??) there's a hefty bill for the suspension maintenance schedule - quite aside from the cost of the initial conversion.

Talk to an engineer Matt, and see how they interpret that.  Perhaps they will.

Quick count I think there's at least 16 pivots/mounts that could go to uniball in an R chassis.  At ~ $100 per joint for quality replacement (no sane person would install low quality sphericals - would they??) there's a hefty bill for the suspension maintenance schedule - quite aside from the cost of the initial conversion.



I was going to approach an engineer until October 2014 when my R33 was written off in a flood. I had adjustable arms with spherical bearings on it and was a little concerned about defects.

I'll admit that if I were to do it again, I'd probably choose bushes over bearings... In hindsight the increase in NVH, the cost of replacement bearings and the stress of law enforcement attention (if engineered or not) just wasn't worth the "increased performance" (not that I could tell, I was replacing 15 year old OEM bushes with bearings, of course there was going to be a performance increase). Unless it were a dedicated track car, which I don't see my finances being good enough to handle at the moment [emoji23]

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