upper arm with poly fail

[deathwishracer]

So, I had installed a bmr upper arm with spherical, then went with a spherical in the rear end housing. Kelly had stated that there would be nothing holding the arm straight, since both ends were spherical. So I switched to a poly arm. Raced it on the street maybe 5 times, never went to the track, or ran my radials, it already busted the poly. So I reinstalled my spherical arm, and used strut bushings on each side in the mount to hold it straight. Works great, don't have to worry about busted poly. Can't load pics from phone, I'll add them later

 

[Sharad]

Smart move!

BTW, there's nothing wrong with spherical on both ends. The arm rotating does not change length or geometry in the suspension.

 

[deathwishracer]

Yeah, it was just adding to nvh I think. It's not too bad now, since the bushings keep everything straight.

 

[BMR Tech]

Yeah, bearing UCA is definitely the way to go.

Poly UCA on autos can be fine, but hitting them with a stick trans - it's hit or miss.

Good thinking on the strut bushings! I am actually working on some custom bushings for our sphericals, but I am not sure that they will be something we offer anytime soon. A Rod-End is easy, you just use a Seals It (RERS-3)...but we prefer not to use a rod-end on a 3-Link.

If it was our UCA/Bushing that failed, let me know and I will get a new one out to you.

 

[deathwishracer]

By the way Kelly, that is an arm I bought from Roush, said to be made by BMR. Does that look correct?

 

[BMR Tech]

By the way Kelly, that is an arm I bought from Roush, said to be made by BMR. Does that look correct?

I can only answer that question, based on; Who told you that we made that UCA for Roush?

 

[BMR Tech]

We used to offer this UCA. We stopped because the cost to manufacture it was just too high.

 

[deathwishracer]

Yeah, that 1 on the left is it, mine is silver. I assume if it was made by BMR, the quality is good? Roush advertised it as produced by BMR for Roush

 

[BMR Tech]

Okay, then yes - we make that arm.

The quality is very good. That specific UCA, to be honest....is about the highest quality UCA you could even produce for these cars. Formed body (strongest design possible) combined with CNC Stainless Spacers, and an FK Spherical Bearing....housed in a CNC Machined Bearing Cup.....it doesn't get any better.

The downfall, no adjustment.

 

[deathwishracer]

Awesome, glad it's a quality piece. The nvh is not that bad with spherical at both ends. No fear of busting poly at the track