Aftermarket Adjustable UCA - Added NVH & Poly Bushing Issues?

[Fiddler49]

Went down the rabbit hole many have gone and bought suspension upgrades. Ordered with the following:

Steeda Boss lowering springs
Steeda heavy duty C/C plates
Steeda adjustable panhard bar
Steeda LCA's w/ poly ends
Steeda adjustable UCA w/ poly end
FRPP relocation brackets

After reading several posts regarding UCA's, I'm now wondering if I need/want the UCA. My understanding is that it's needed to readjust the pinion angle after lowering the car. However I'm confused as to why changing out the OEM UCA with an adjustable UCA with a poly bushing will increase NVH, according to various comments. Also I've seen posts and pics of failed poly bushings, specifically with the Steeda. Again, why would this be a bigger problem than with OEM?

 

[Surfergeek]

I have been through a few revisions on my UCA.

Stock (non-adjustable and difficult to correct pinion angle when lowering the car, especially if you put in a 1 piece driveshaft)

Whiteline, no increase in NVH and you can adjust pinion angle, however, at my power level the bushing couldn't take it.

I now have a BMR with a poly bushing. Huge improvement in forward bite, but I also get more NVH.

NVH with a poly or even worse with a spherical bushing will come in the form of gear whine, which you haven't heard before. It gets transmitted through the diff, through the arm and into the cabin, as the mount sits right below the rear seats. Spherical bushings are race car loud and not recommended for the street, but the poly bushing doesn't get rid of 100% of the NVH.

Some of it can be dealt with by dynamat and noise deadening in the area and on the bolt for the upper control arm, but you won't be able to get rid of it all.

I would look at the BMR arms as well: http://www.summitracing.com/parts/bmr-utca032h

and the associated: http://www.summitracing.com/parts/bmr-ucm002h

The nice part of the BMR, is it's adjustable and you can actually adjust the arm to fix pinion angle specific to your suspension. Now, since you are going full Steeda, it's probably at the right length for the springs and lower control arms you are putting on, so maybe not as important to have that adjustability.

 

[VoodooBoss]

You know what I think.

Not sure the pinion angle is going to be a problem. For the limited amount of track time you do I'd hold off until you think you need it. You'll notice an improvement with the other items you purchased.

 

[TymeSlayer]

I have been through a few revisions on my UCA.

Stock (non-adjustable and difficult to correct pinion angle when lowering the car, especially if you put in a 1 piece driveshaft)

Whiteline, no increase in NVH and you can adjust pinion angle, however, at my power level the bushing couldn't take it.

I now have a BMR with a poly bushing. Huge improvement in forward bite, but I also get more NVH.

NVH with a poly or even worse with a spherical bushing will come in the form of gear whine, which you haven't heard before. It gets transmitted through the diff, through the arm and into the cabin, as the mount sits right below the rear seats. Spherical bushings are race car loud and not recommended for the street, but the poly bushing doesn't get rid of 100% of the NVH.

Some of it can be dealt with by dynamat and noise deadening in the area and on the bolt for the upper control arm, but you won't be able to get rid of it all.

I would look at the BMR arms as well: http://www.summitracing.com/parts/bmr-utca032h

and the associated: http://www.summitracing.com/parts/bmr-ucm002h

The nice part of the BMR, is it's adjustable and you can actually adjust the arm to fix pinion angle specific to your suspension. Now, since you are going full Steeda, it's probably at the right length for the springs and lower control arms you are putting on, so maybe not as important to have that adjustability.

Have my Boss lowered with a one piece DSS driveshaft and the following BMR components: Adjustable UCA (poly) & relocation bracket, LCAs with adjustable bracket and panhard bar. After installing the UCA, I too anticipated some new NVH but not sure that their bracket helped but there was nothing noticeable in that department. There is a bit of gear whine but it's not too bad at all.

 

[Fiddler49]

...NVH with a poly or even worse with a spherical bushing will come in the form of gear whine, which you haven't heard before. It gets transmitted through the diff, through the arm and into the cabin, as the mount sits right below the rear seats. Spherical bushings are race car loud and not recommended for the street, but the poly bushing doesn't get rid of 100% of the NVH. ..

Thanks for this info Surfergeek! What I was looking for...

Appreciate everyone's experience with UCA's. Seems to be a lot of different opinions/experiences with them.

 

[302 Hi Pro]

Anyone have experience with the Roush non adjustable UCA? Seems to look like a beefed up OEM style UCA that takes out excessive play.

This also looks similar to the MultiMatic approach to the UCA design. Anyone know about this UCA? Is this a Bush or Joint type UCA assembly?

Thanks,
Dave
2HP

 

[Tri-bar]

The Roush upper is a bushing, it's smaller and stiffer with wielded reinforcements over the bushing.

 

[BMRTech]

Man, all this Poly UCA talk is making me nervous.

If you guys are tracking your cars, IMO, putting a poly up top is a bad idea on the 3-Link System.

In that case, I would honestly recommend something more along the lines of a Roush UCA and a Spherical Diff Bushing.

As for the MultiMatic piece, I wouldn't spend the extra money for that when you can get the spectacular 1" Bearing UTCA033 we make. It is the strongest and best designed UCA on the planet for the S197.

 

[BMRTech]

Sorry, I forgot to mention the Poly failures.

Polyurethane (yes, the "Elastomer" falls into this category too) - tends to deform. You will see many people call it "cold flow".

When this happens, you break the compound down, or push it past it's ability to snap back (from elasticity) and it will permanently deform. The deformation increases the odds of the bushing splitting/cracking when the shock loads are applied.

Most of the time when a Poly bushing fails, it is due to increased shock loads and varying angled loads. Poly is just not a good material for articulation characteristics.

 

[TMSBOSS]

I agree the steel bearing is the strongest possible solution. But, many of us enjoy driving our cars away from the track and would prefer to Not hear the gear noise only.

Is there a good poly bushing you would recommend along with a replacement cycle. If its going to fail, how often should we swap out the bushing?

 

[Mad Hatter]

A little off topic, Sorry. But getting a BMR watts link is a bit more expensive and leaves the UCA obsolete I think. Seems like a lot more benefit for the money.

 

[TMSBOSS]

A torque arm/tube removes the UCA. You will need the UCA with the watts link. The Watts link replaced the Panhard Bar.

 

[Mad Hatter]

Thanks for the correction!

 

[TymeSlayer]

A torque arm/tube removes the UCA. You will need the UCA with the watts link. The Watts link replaced the Panhard Bar.

This is correct. I have been thinking of getting that BMR Watts link.

I have the poly bushing and it's working great on my UCA but I only get the car on track for 2-4 tymes a year. I think the poly is fine for my needs and if it does deform, I have a spare and can throw in a new one. It's not overly difficult at all. If there is a better solution without all the NVH, I'm listening.

By the way Mr. BMRTech - I thought the UCA mount I got from BMR was advertised to keep noise down, yes?

 

[TMSBOSS]

TS
Once you remove the factory bushing on the Diff. how involved is it to swap in and out a new poly bushing?

 

[TymeSlayer]

TS
Once you remove the factory bushing on the Diff. how involved is it to swap in and out a new poly bushing?

Once you've put in a poly bushing it becomes rather simple. Remove the UCA bolt, pull out the two piece bushing - this can be tricky but punching out the inner sleeve with make removing the two piece bushing easier to remove. Replace and use a c-clamp to press in the new. Can be done in 20-30 minutes.

NOTE: If you have the OEM rubber still in there, it will require removal and it'll take a bit longer.

 

[TMSBOSS]

Once you've put in a poly bushing it becomes rather simple. Remove the UCA bolt, pull out the two piece bushing - this can be tricky but punching out the inner sleeve with make removing the two piece bushing easier to remove. Replace and use a c-clamp to press in the new. Can be done in 20-30 minutes.

NOTE: If you have the OEM rubber still in there, it will require removal and it'll take a bit longer.

Got it. Thanks

 

[Tri-bar]

I'm running this bushing with my Kenny Brown upper. It lets the upper move, not a lot a noise.
http://www.steeda.com/steeda-upper-control-arm-bushing-kit-555-4436/

 

[drano38]

I'm still running the stock UCA. Check the fittings routinely, and they're still good.
From the posts I've read over the last few years, it seems an upgraded poly UCA causes all the twisting stress to be absorbed by the stock diff bushing--which wears it out.
When/if I replace mine, I'll probably go poly on the car side and install a spherical in the diff end.
http://www.steeda.com/steeda-mustang-spherical-bearing-555-4104/

I don't drive it on the street much so I can accept the NVH. And my UMI LCAs are poly on the body and Roto joints on the axle--I get some NVH, but not bad.

 

[Fiddler49]

So to distill down what I'm getting out of this discussion is that poly bushing UCA's:

• could see failure of the poly bushing with road track use
• could cause failure of the stock diff bushing with road track use
• could be marginally useful on the drag strip (may be extrapolating here)

If this is the case, then why are there so many different flavors on the market? Why was Steeda so adamant that I needed an adjustable UCA to correct pinion angle? Am I just a sucker for marketing hype???