Banana arm bushing question for 72

[tobluforu]

I'm replacing the bushings on my trailing arms. The old bushings that i took off have a metal sleave that is surrounded by rubber and is pressed into the banana arm. The new ones that i received from pelican are JUST solid stiff rubber that if pressed hard enough will fit into banana arm. Are these bushings the right type? There is no way that the new rubber bushings will slide onto the original metal sleave.
thanks

------------------
72 911T

[Evans, Marv]

I have the same kind of bushing I'll be installing in my '72. I don't believe you have to have the metal, inner sleeve in the new bushing. If you want to put it in, you can always drill out the bushing to accept the sleeve.

------------------
Marv Evans
'72 911E

[Formerly Steve Wilkinson]

I've been told by somebody who should know--a former national-champion autocrosser--that those hard, noncompliant bushings are a big mistake for the banana arms. Those arms have to move in three dimensions, not simply linearly, and if you put the noncompliant bushings in, it does bad things to the handling. I had them in mine and took them out and replaced them with the stock OEM bushings before ever running the hard ones, as a result. So I can't vouch for what my friend said, but I do believe him based on his rep as a 911 suspension tuner.

Stephan

[piperpilotduane]

I have them in my '76 912E and have had no problems. My car rides and handles better now than before, but the ones that were in it were rotten. Unless you are going to compete (for Money) with your car I would not worry about them.

------------------
Duane
'76 912E, '73 914,
& '76 VW BUS (ALL 2.0L)

[chrisp]

I had a poly bushing company who makes bushings for the 911 rear control arm "suggest" that I go somewhere else. They too are concerned about the multi axis movement of that bushing. Although they did not sell them, they recommended the spherical bearing set-up which I purchased and am happy with. For the record their rationale for selling the 911 control arm poly bushing was that "some people want them so we need to have a product to sell them".

I don't think we're talking about a durability or safety issue here. I don't think that if you have poly bushing your control arms are going to fall off or anything like that...I just think in order of best performance, top to bottom, it would go 1.) Spherical bearing, 2.) OEM rubber bushing, and 3.) Poly bushing.

[tobluforu]

The spherical bearing ones are really expensive are they not. Do the stock oem bushings have the metal insert? If so, i think these would be a better choice than the solid rubber ones-am i right?

[tobluforu]

For anyone that cares. First porsche shop i go to, one mechanic says stay away from the poly bushings. They squeek, need to be lubed every six months. Same shop, dif. mechanic-poly bushings are great, much better than oem. Hmmmmmm
Go to another shop-which is pretty much a race shop. Ask the owner the same question. Poly bushings suck! If your driving hard, alighnment will change. When you tighten them down they squish to much. Bolt wears a nasty groove in them. After 2 years time they need to be replaced. So HE says. His reccomendation-mono ball. Yea right, like I'm spending 350 on bushings. Actually, if i was'nt jobless i would have probably bought them. His next reccomendation-OEM!
So, OEM it is. Could have saved some time and just listened to warren.
Looks like chrisp is the winner.
Anyone want to but some poly bushings-just kidding.
Thanks all

[Randy W]

Monoballs are the absolute best option for the inner control arms - many club racers use them. Unfortunately, they are not legal for SCCA stock and street prepared autocrossing. I know Dwight Mitchell does not recommend the poly bushings as they can bind. However, I believe they do provide more direct feedback than OEM, are easily available, and work well enough if installed by an experienced autocross tuner.

Randy Wells

[tobluforu]

Here i go again. As to what marv mentioned, my neighbor has a drill press-actually the guy has almost any tool a home mechanic could ever wish for. Any one drilled out the poly bushings and fitted them over the metal sleave? Would this work? Kind of the best of both worlds???-maybe..

[RoninLB]

Anyone have hard info on using poly in the upper rear control arm ?

[Pat S]

I ordered the poly's but haven't installed them yet. I've also been told (probably from the same source you all are describing) not to use them.

We need some input from Chuck or the other suspension experts here I think...

[jpachard]

Poly Bushings fight your alignment settings. If you are trying to obtain more negative camber then you can run into problems. Otherwise, they are a viable option. As I remember, there are several durometers available in the poly bushings.

Cheers, James

[tobluforu]

How did this get resurrected? Damn what's up with my great spelling? Well since this came back up, and after all the ?'s, I went w\Monoball's after all.

[Chuck Moreland]

I don't recommend the poly replacements for the inner trailing arm link for anyone. Polyurethane is poorly suited to this application and should not be used.

As above, they fight the required motion of the trailing arm - which needs to move on multiple axis. They also lack the center steel sleeve.

In the factory design, the center steel sleeve supports the load of the tightened bolt, in compression. The poly replacements have no sleeve. Hence the load of the bolt squeezes the polyurethane tightly into the sides of the trailing arm. Pinching it! No wonder these things bind!

Monoballs are the best performing solution allowing free movement in all axis, with a central sleeve to support the bolt load.

The factory rubber replacement type is a good choice when factory level performance is acceptable.

[RoninLB]

thanks everyone.
I couldn't find a clear explan for the banana arm bushing after doing the "search".