Rear suspension bushing choices/thoughts
 

Need some help getting out of my analysis paralysis and picking which rear suspension bushings to go with. The car is a 1969 911E with a 3.4 Motronic motor, upgraded the rear banana arms to the later aluminum style which have the Elephant Racing monoball inner bushings. The fronts are all ER polybronze bushings. Adjustable ER front and rear sway bars.

The problem I'm having is choosing the rear spring plate bushings. I have the ER polybronze on my 1985 and love them, but greasing them is a real pain and creates a bit of a mess under the spring plates that is tough to keep clean.

My choices and the plus/minus for each:
ER polybronze - excellent performance but pain to grease and messy

Rebel Racing - excellent performance but not excited about JB welding anything to the car itself. Would be real pain if I ever wanted to replace. Also the most expensive option.

Rubber of some sort - probably can get decent performance but too many choices and horror stories about early failure and difficulty properly bonding to the spring plates. Also a pain to set the ride height if the inner rubber gets stuck in the car. Least expensive option.

Hard plastic (the ones that come with the Weltermesiter adjustable spring plates) - decent performance but they can squeak. Any other issues with these?

I'm leaning towards the Rebel Racing option as it is the highest performance without the headache of grease/maintenance. Any thoughts on how hard it would be to remove and clean up the chassis if I decided to go another direction. If I want to go with Rubber what is the best option here (ER, URO, Prekom, other)?

Thanks for any thoughts/help!!
Bill

Gratuitous pic of the car:

http://forums.pelicanparts.com/uploa...1654610827.jpg

Bill, the stock durometer rubber is best if you choose rubber, that is what is used in many active rally cars today. My best and Fav is Rebel Racing , the can be shipped the day you order them from Tarret, By far the best and smoothest .
Just my thoughts
Ian

I have poly bushings in my '87 that worked well and recently installed the Rebel ones in my rally car. Fitting took some work and after freezing the sleeves, I did't need to JB weld them. So far so good and on a rally car, so they will see abuse.

Rebel racing fan here. If you have to pull them out use heat and a slide hammer. Not easy but doable.

http://forums.pelicanparts.com/uploa...1654628161.jpg
http://forums.pelicanparts.com/uploa...1654628161.jpg
http://forums.pelicanparts.com/uploa...1654628161.jpg

Thanks guys, really leaning towards the Rebel Racing solution. There is now some additional support from Erik at Sports Purpose Garage so I have some confidence I can actually get them now. Our host carries them, but showing out of stock :-(

This might help.

<iframe frameborder="0" scrolling="no" marginheight="0" marginwidth="0"width="788.54" height="443" type="text/html" src="https://www.youtube.com/embed/2MEVqLu_FqU?autoplay=0&fs=0&iv_load_policy=3&showi nfo=0&rel=0&cc_load_policy=0&start=0&end=0&origin= https://youtubeembedcode.com"><div><small><a href="https://youtubeembedcode.com/pl/">youtubeembedcode pl</a></small></div><div><small><a href="https://xn--utlndskacasinomedtrustly-sbc.se/">https://xn--utlndskacasinomedtrustly-sbc.se/</a></small></div></iframe>

I had to take some material off both of the rear sleeves to get them to fit. I used the JB weld but don’t think it was needed, they were a very tight fit.

Ditto what Ian said- I ordered adjustable spring plates with the bushing already vulcanized to them from Rebel and the are wonderful.

You mean your favorite is the Rebel solid bushings? I don't see any Rebel Racing rubber bushings (Tarett carries rubber, but they don't say whose).

Edit - looks like the Rebel Racing adjustable spring plates come with the rubber bushings already installed - is this the case?

Bill

Yes, the adjustable spring plates have the rubber bushings already vulcanized to the metal.

Hard plastic/rubber is right out. They tend to squeak and suffer worse performance than the spherical bushings with just as much harshness. They last until you get fed up and replace them.

The Elephant/Rebel spherical suckers make your ride softer and more predictable, with the possible down side of increased road noise (though from my own research here, it seems like this isn't noticeable or everyone who installs these already has a loud car). My pick is RR here, as they don't require greasing, but I have yet to drive on a set of either.

Rubber is rubber. Pretty damn good for a decade or so.

As stated yes the spring plates come with the rubber bushings installed. It would be nice if they weren’t installed when going with the rebel racing bushings. Maybe when you order you should ask them if you can get the spring plates without the rubber installed, I didn’t see that as an option but maybe it is. You have to heat up the rubber to get them off so it’s a waste of new bushings.

WJ - Leaf Green?
Had a 70E 15 years ago in that color - I am an idiot for selling it.

duplicate post...

No, it's 1978 Olive Green. The car was originally the 1969 Olive Green which in know is a very rare and some might say desirable color, but I just could not make myself like it. So the door jam sticker says Olive, and the car is still Olive but I actually like this one :-)

Very long story behind this car, once I finish spending all my free time in the garage I will start a build thread from the beginning.

On the suspension bushing, I decided to go with the ER polybronze. I love them in my '85, install is a breeze and right now cannot find anyone who has stock of the Rebel Racing bushings. I also hear from Erik (the new front end rep for RR) that they have the inner bushings machined down .03" to alleviate any fitment issues on the torsion tube.

Once I have the rest of the car set up and running, I may upgrade the spring plates to the ER adjustables and I can try rubber bushings at that point. Thanks for all the help/suggestions.

I installed ER rubber bushings on my 69E hotrod. Very pleased with the ride compliance and install of those. I did them probably 7 years ago and they are holding up well.

I’ve had/have 911’s with monoballs, Delrin bushings, ER poly bronze, and fresh rubber. Unless a car is predominately track use, I am now a firm proponent of fresh rubber bushings. I find their compliance and additional isolation of NVH more than makes up for any increased stiction compared to poly bronze or similar bushings. Just my $0.02.

Can you expand further on the NVH impact of the ER polybronze bushings and rubber? Did your car get noticeably louder? Did you make any other changes at the same time?

The polybronze and similar hard bushing may be smooth in their movement, but they do not isolate vibrations and impacts from the chassis. A good example are expansion joints in roads. When your tire hits a bad one that is sticking up, the wheel gets forced rearward while trying to move up and over the bump. The hard bushings have no compliance so that rearward component of the impact is transferred directly to the chassis as force and noise. A rubber bushing will absorbed some of that rearward impact and absorb some of the energy before it is transferred to the chassis.

More granular road noise is also transferred to the car by these bushings. Yes they can/do provide superior performance, but I feel for a road car the trade off in NVH is not worth it.

I had poly bronze on my backdated gulf blue turbo car. I have delrin and mono balls on my ‘69 ST. I put all rubber in my current ‘74 build, and when it’s done the ST will get rubber bushings too, even though I track that car most.