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Bmr Spherical Uca Install


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I got a chance to install the BMR Spherical Upper Control Arm and bracket last weekend and wanted to share some feedback on the install, the drivability impact and some tips to help with the process.

Setup: Race ramps, creeper, air tools, power tools, lots of sockets and wrenches

Parts: The BMR spherical UCA and bracket are a work of art. Great craftsmanship, very sturdy and they looks great. Here's a side-by-side look with the stocker:


Install: Everything was straight forward using the BMR guide. The rear seat bolt took a long breaker bar and cheater pipe to get it loose, but it finally went.

The two 18mm bolts on the rear bracket are tough to remove since they are way up under the car and have blue Loctite on them. Power tools or air tools are a lifesaver here.

I had to lower the fuel tank, which was very simple, using a T50 torx bit. I spun the bolts in and out a few times to break them free. Using a jack under the tank, I slowly lower one side, placed a jack stand underneath and repeated on the other side. It will eventually rest on the driveshaft. This part seemed scary, but was really easy. Make sure the fuel tank is near empty to make things easier.

Getting the axle end bolt in was a little tricky. Lifting the axle from the rear section is required so everything articulates properly into place. Lifting at the front part of the pumpkin will not rotate the axle properly for the UCA bolt to line up. (1.5 hours)

Adjustment: Setting pinion angle was not too bad, but I made a rookie mistake at first. I was measuring from the rear of the transaxle and was supposed to be measuring from the pinion flange. I figured this out quickly after my first test drive. Eventually got a -3 degree angle and was set.

It is critical to get the jam nuts very secure before finishing up. This is the most critical step and the most difficult one since there is a little room to work. I used channel locks, but a 1.5” wrench would have been a dream to have. My first two rounds, I didn’t get the nut tight enough and ended up re-doing my work. I also think giving the Loctite several hours to cure helps keep the jam nut in place. (1 hour on day 1, 1.5 hours on day 2, 1 hour on day 3)

Driving impression: WOW. I expected some improvement with wheel hop, but I got much more. Taking corners quickly feels completely different now, with the back-end squatting firmly. But the bigger surprise was going from 30-to-50 at WOT…The back end squatted (very noticeable), tires grabbed and I took off like a rocket. I haven’t tried a hard launch from zero yet, but I expect the same ‘tire grabbing’ feeling. This is the way a GT500 should feel. BTW, NVH is minimal...Maybe a little more gear\trans noise, but it's barely noticeable for DD.

Things to note:

- Working on ramps very doable. Air tools make life much better!

- Set the jam nuts right the first time. Use lots of Loctite and spin the nut with lots of force (120-150 ft\lbs). Practice the direction the nuts spin before you do the install (this would have saved me 1+ hours). If the nuts back off, the upper end of the arm will rotate on its side and cause a loud “click” noise when you shift or hit bumps. I wish I could tell you how annoying this sounds…oh wait, here’s a link.Otherwise, the end of the arm will touch the bracket and this is not good. The front end of the arm (with the spherical bushing) should be squared/centered up on install. If you lift the car back up and see this, you probably didn’t tighten the jam nuts enough. (Pictures are example of a BAD job...notice front end rotation)


Summary: Great purchase overall. This completed all my suspension mods. It was very challenging, but learned a lot. Please shoot me a note if you have any question. BTW, huge thanks to Kelly at BMR for being responsive via email and the phone. Really appreciate the help! Super service and super product.

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What are you going to do with your old OEM UCA ? I need some OEM 2011+ ones for some testing purposes.


I'd be happy to send it your way if you pick up the shipping cost. PM me your zip and I will get an estimate.

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Great real world install write up! Kelly at BMR is the man- very helpful and responsive. Installed my UCA and Bracket last weekend and it went really smooth. Matching the stock length exactly and tightening it down on the bench resulted in my pinion angle @ 2*, spot on. I was surprised since the car is lowered.

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