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There is a thread on MT.net that shows a badly damaged shock body, caused by the shock contacting the FUCA. Supposedly worse in NB8Bs, because of some reinforcing applied to that part of the arm. It is suggested that the ELBJs are indirectly the cause, as with the ELBJs the factory camber adjusters are wound back, pulling the FLCA closer to the car and the shock body closer to the edge of the FUCA, and allowing the shock to make contact with the FUCA especially towards full compression.

It is not an epidemic over there, but there are isolated instances. One fix that is used is to grind out the clearance on the FUCA a few mm, at least with the reinforced arms. This seems like a sensible precaution.

Has anyone here experienced this after fitting ELBJs? If 'yes', do you know what camber settings you were running at the time, and whether you were running NA or NB FUCAs? How did you fix the issue? I know of one local who has experienced this issue, fortunately in a minor way (paging ML )

The subject is of interest to me, as I am about to fit my set of ELBJs ...

So many acronyms.

Front Upper Control Arm
Front Lower Control Arm
Extended Lower Ball Joint

I commented on the MT.net thread. I have slight grazing on my passenger side shock body, threads are bent slightly, but not gouged like the badly damaged shots.

The badly damaged shock was in a track car that sees sustained high level cornering forces, ie the corkscrew at Laguna Seca, those aren't conditions I would experience normally in my street driving.

One of the members on MT.net said he put some tape around his shock body to detect any wear (he didn't find any after a test at a track day, but he wasn't using NB8B FUCAs). This seems like a good test for me to check the cause of the damage I see to ensure it's not the result my ham-fistedness while working on the car.

My understanding of the issue was that it arose from fitting ELbJ’s and then using the stock camber adjustment of the lower arm to pull out negative camber (back towards a more normal setting for street), and in so doing, move the shock lower mount inwards and the shock body towards the inner of the upper arm.

I thought this was a street car with track car parts issue (not a track car issue)

You've described the cause pretty accurately. It's an issue caused by ELBJs combined with NB8B FUCA. The shock body used makes no difference, other than maybe a really thin one would be less likely to impact.

He, MiataMan00, was running -3.0*, its a street registered car, but he runs a splitter and a wing on track which makes it pretty much a track car IMO. Sure, he could have had more camber, but the gouging on his is quite extreme, I don't think another degree would have alleviated the problem.


MiataMan00's Xidas on MT.net


MiataMan00's Xidas on MT.net

FWIW, I'm running only -2.0* (because the alignment guy ignored my request for -2.5*).

Supermiata shows the difference the gusset makes:


And Goodwin shows what you might want to do about it:

https://www.mazdatalkforum.com/viewtopic.php?f=9&t=3337&p=20334&hilit=control+arm

Early days yet, but at least we haven't had a ton of people coming here saying it happened to them, so that is comforting.

As you point out Lachy, that was with -3*, quite a respectable amount of neg camber (from memory his adjusters are around the mid point). I am unconvinced that the MiataMan example is simply due to the position of the camber adjusters and full compression, I suspect there is something more, but whether anything emerges from that thread to definitively nail it remains to be seen. In the meantime I will be taking the springs off my shock body and checking for clearance over the full movement when the ELBJs go on, and maybe doing some preventative grinding for the removal of doubt.

I was going to swap in the FUCAs from the late lamented GM (an NB8A), but it turns out it had the later arms, not sure how that came about. At least I can do the grinding and bushes at leisure.

Thanks all for your contributions

GM, I'm curious to see the results of your travel check. I did a travel check when installing my new springs a few months ago, and while this was with the SADFab retrofit kit fitted to the FUCA, the lower arm was still stock, including LBJ.

I will tape my shocks up this weekend and see if any wear develops in my daily driving.

I will report back, Lachy.

Unlike you, my car is being tracked, so it is likely to experience more shock travel combined with bushings deflecting under high loads.

(Thanks Wilko)

A road car will experience the same shock movement under (severe) bump conditions, but not the side loadings of high 'G' cornering with sticky R-specs.

My car is meant to get tracked from time to time It'll be a daily driver for a while yet, but one day I'll get back out there!

I saw the same thread on MT.net. I'll be fitting the ELBJs on my SE soon, and thought I'd just take the preventative measure of grinding away the FUCA as suggested.

Another data point...

I just checked mine. I have ELBJ’s and am sitting at -4 degrees camber. I have the NB2 upper arms.

I’m using very soft and sticky rubber and make use of most/all the suspension travel. There has been no contact for me.

I wonder if ride height and shock body length play a role in this. More ride height means more compression travel which means more opportunity for the lower arm to fold up and in...

Different diameter shock bodies at play here as well? What are you running?

SKYHI wrote:Different diameter shock bodies at play here as well? What are you running?

MCA (and previously Tein)