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Am I Good Enough For Multimatic Hardware? (Rear Upper Control Arm)

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303
371
CA
Hello Everyone,

At 175k miles and 2 seasons on 315's, I fear the original rear upper control arm in my car is absolutely toast. I have been doing some research on replacing it and have come up with some thoughts/opinions/criteria.

The following is my criteria:
1.) Effectiveness at improving feel and stability of the rear end
2.) Durability
3.) Serviceability
4.) Streetability (Car has a rollbar and no rear interior, so this isn't a huge deal at this point)

What I am looking for is a durable, effective, set it and forget it solution. That's also still street-able. I am lazy, and gasp at the thought of people who replace/inspect parts "every season".

Given this criteria, am I mad to think the multimatic arm seems like a genuine solution? For those of you that have this arm, what is the service life of the spherical bearing? Is the NVH unbearable? Any noticeable difference compared to the more "normal" options out there? (Roush 3rd link, steeda, BMR, etc.)

What setup would you do if you were in my shoes?

I look forward to your replies!
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
I would get the BMR UCA support and leave the stock arm or a poly one... If I remember right, @ajaquilante must have had a stock one in the Phoenix 33 super fast S197, pretty sure that was mandated by the rules.. I truely hated my two spherical arms.
 
Last edited:
303
371
CA
What didn't you like about the spherical arms? By arm(s), which do you mean?
I would get the BMR UCA support and leave the stock arm or a poly one... If I remember right, @ajaquilante had a stock one in the Phoenix 33 super fast S197. I truely hated my two spherical arms.
What didn't you like about the spherical? Odd handling? Bad ride? Too loud?

Trying to absorb all the info I can....

Appreciate it 👍
 

Mad Hatter

Gotta go Faster
5,237
4,227
Santiago, Chile
Really really loud after about 4 races... barely any change at all over stock setup as far as handling goes, At least none that I detected. Would not wish that horrible noise on anyone. And most of the car had already has been changed to Spherical.

its probably the worst upgrade I have ever done. :banghead:
 
179
67
ny
On a fr500c if you go bearing you have to do all 3rd link and lca on rear. I have cortex watts link all heim jointed roush adjustable lca with heims and boxed roush 3rd link with spherical bearing and steeda bearing In rear.no rubber/ poly anything. I love the way the rear handles compared to panhard bar.
I also have the multimatic 3rd link. I also changed out roush steel swedge tubes to aluminum.
 
179
309
Utah
My car came with a Cortex Watts link, multimatic UCA, 1/2 inch Watson sway bar and Maximum Motorsports LCA. All hiem joints. I can’t attribute any handling woes to the UCA in particular, but due to the spring rates and such being so off, it took a few track days to settle the rear down. (Penske dampers for the record). Tried no bar etc. but went back to the Watson bar.

I went to a single piece drive shaft and a BMR adjustable UCA so I could set the pinion angle. I drove it a few more weekends. No real improvement other than the noticeable benefit of the one piece driveshaft.

So over the winter, I installed the Cortex Torque Arm (UCA not necessary and the pinion angle is set). This alone was a huge benefit to planting the rear and making it very predictable. I would say it is the best rear mod for the S197 since the Torsten diff.

I do have the Watts link, which I think works very well to be able to adjust the roll center (I’m running on the bottom hole) but there are other ways to skin that cat.
 
6,362
8,185
My car came with a Cortex Watts link, multimatic UCA, 1/2 inch Watson sway bar and Maximum Motorsports LCA. All hiem joints. I can’t attribute any handling woes to the UCA in particular, but due to the spring rates and such being so off, it took a few track days to settle the rear down. (Penske dampers for the record). Tried no bar etc. but went back to the Watson bar.

I went to a single piece drive shaft and a BMR adjustable UCA so I could set the pinion angle. I drove it a few more weekends. No real improvement other than the noticeable benefit of the one piece driveshaft.

So over the winter, I installed the Cortex Torque Arm (UCA not necessary and the pinion angle is set). This alone was a huge benefit to planting the rear and making it very predictable. I would say it is the best rear mod for the S197 since the Torsten diff.

I do have the Watts link, which I think works very well to be able to adjust the roll center (I’m running on the bottom hole) but there are other ways to skin that cat.
The Cortex torque arm ( or truck arm for us southern redneck types) is usually a worthwhile investment. As for the rest, I would highly recommend staying with a stock or Gt500 upper trailing arm.
 

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