Has anyone here used liquid urethane in their bushings?

[BigKriss]

Still sorting out what bushings to use in the thrust arms. I would appreciate comments of it’s use it the subframe bushings also.

Here’s a previous post on the use of liquid urethane;

http://www.bimmer.info/forum/showthread.php?t=3424&highlight=liquid+urethane


Bruno recommended to me to use M5 bushings filled with liquid urethane. Are there any writeups for this procedure? I’m thinking this is the way to go for the thrust arms.

[niall]

Wtf???

[Rory535i]

dude i'd either go for the M5 bushes or poly ones. I wouldn't be bothered messing around with all that.

[JAlfredPrufrock]

Anyone know what all the M5 bushings would cost from the stealer?

[BigKriss]

There been a lot of bad rep from polyurethane bushings recently. I'm having second thoughts on using them now. Brett Anderson replied back saying that the best setup is to.. "Put E34 M5 thrust rod bushings and new thrust rods on the car and replace your lower control arms with stock"

[niall]

kriss i really dont understand what you are looking for,

do you want track handling or stock handling????????

[BigKriss]

Hi Niall, of course I want the car for track handling, the faster I can take a corner the better :) I was originally thinking to go for RRT control arms (you can see some of their products here - no e34's ones listed though (http://www.roadracetech.com/performance_catalog/products/suspension.asp)).

They want us$230 per arm each (steel upper and lower), pretty expensive I think. Twice the price of a lemforder arm with a m5 bushing. John Teeples from the board is running them. His only critial comment of the was (don't quote me on this) is that you feel every nuicance on the road.

I was then thinking polureathne bushings would be the way to go untill I started reading the UCC mailing list and their negative repsosonses about urethane bushings for the upper control arms.

What negative repsonses are they saying;

- "I'm reluctant to replace my upper control arm bushings with urethane on account of the 4x higher stiffness that comes with the increase in durometer (55 to 90 durometerA?). This would lead to accelerated wear of other parts in the car, primarily ball joints."

- "Because the stock rubber component firmly grabs the bushing holder and the control arm, therefore, it is an active member of the suspension and it's resistance to movement. "U"rethane on the other hand simply allows the control arm to spin within it, not providing any resistance at all."

hmmmmmmm. I do love the thought of urethane bushings,but it's pretty uncharted waters for our cars. thats all.

Maybe the older gentleman on this board care more for a smooth, comfortable ride in their e34. I don't particulary. Remembering back before I replaced the springs and shocks (about 8 months ago), they where old, the car handled poorly, couldn't take corners for crap, the car rolled significantly more however bumps where absorbed a lot better, especially smaller bumps in road. You felt them a lot less in the car.

Now smaller bumps are a lot more noticable. Personally though, I would take the tradeoff anyday. I would never revert back to a stock setup for the suspension. I don't find the increase in feeling bumps annoying.

My main concern is to get polyuretahne bushings on the control arms (upper and lower) that they will wear out other suspension components significantly quicker. hmmm. How's my thinking?

[niall]

kriss the way you drive it, every component on the car
will wear prematurely, my advice, and i asked my boss about this too,
is go for the poly bushes and see how things go, he reckonss
it will be all good, but its up to you mate

[BigKriss]

Thanks Nial, I will update you shortly.

[Chip]

Kriss-
I'm running the RRT control arms and the increase in road feel (or road noise) is not as great as when I'm running the 17" wheels rather than the 15" stock wheels. Turn-in is greatly improved and is noticed on the track. I rode in Barry's e34 Touring with both the control arms and thrust arms installed and there was still not much increase in the road noise, but handling is improved even more. If you are setting up to do mostly track driving, then the RRT route would be my recommendation. For your concern of 'that they will wear out other suspension components significantly quicker'- it sounds like you are(/will be) replacing most of those components anyway, so then what's the concern. They are expensive, but will not wear-out.

Good luck and have fun-