Pics of new Neatrix/Elephant ASPs
 

I just got done installing these things, along with new sway bar bushings and Bilstein greens. No problems with the installation, but getting the bushings into the torsion tube took some heavy persuasion with a BFH and a wood block. I lubed them with liquid hand soap first, which I'm sure helped a lot, and when its dry it won't leave them lubricated (which is what we want). The Neatrix bushings were epoxied to the spring plates using Permatex Cold Weld (3000 psi sheer strength). Hopefully they'll stay put and won't allow the spring plates to turn inside them. The Elephant Racing Quick Change ASPs are quality pieces as you would expect, and make some fine Porsche jewelry. Although they were made to work with the Quick Change TB's, I'm using them with the stock 25mm bars because I want to preserve the stock ride quality (street only). Ride height adjustment should be a breeze, unless I have to reindex the dang things. They went on to within 1 degree of the angle that the old ones came off with, but I'm not sure what effect the Bilsteins and new bushings might have on where the car settles. I'm without wheels at the moment so I can't let the car down for a few more days. I also had the front A-arms reconditioned with new rubber bushings, and did the front sway bushings, turbo tie rods, and Bilstein greens there too.

http://forums.pelicanparts.com/uploa...1225574791.jpg

No lube on the outside and epoxied on the inside. What turns?

Rubber flexes like from the factory.

That's a lot of flex. Seems to me that at full droop, it would tear. I have a feeling that the original vulcanized bushings were allowed to rotate in the holder when the car was jacked up. Normal suspension travel would not need them to rotate. I went the other route on my '71 and greased the insides of the bushings. Maybe that was wrong, who knows?

I've been reading this stuff for too long anyway. There must be 10 different ways to install rear bushings.

Never thought of this,......never heard of using epoxy,.....then, again, I've never done this job!

...to rotate or not: that is the question?

Best,

Doyle

Well, the original fronts probably didn't rotate even at full droop. But, they were really soft rubber when new. So soft that both the fronts and the rears would wear so that the arms would no longer be in the center of the holder. Obviously the harder urethane bushings needed to be fitted so that the arm could move. I used those only once on my 914 race car. Many threads on that. It's the Neatrix one that I don't really know about. How soft is it? Mine weren't that soft. And, Neatrix is not offered for fronts that I know of. So, one does not have the option of gluing the fronts. There is no better aftermarket front bushing than Elephant Racing, IMHO. Probably goes for the rears, too, but I've used the Neatrix because of lack of funds for a full ER setup.

When you take out the rear spring plates and try to take the rubber off it is pretty clear they are bonded on the inside of the rubber bushing.

Note the inside has less surface area so would be the first to turn if not bonded or glued.

I guess the outside has the potential to turn if really needed to but the shock restricts angle to some degree if totally jacked up.

The Neatrix bushings used to be delivered with supper glue. For some reason they no longer seem to be.

To install mine, I put only the inner bush on first and used the outer plate to suck it in using the bolts.

Then I put the outer bushing on and used longer bolts to get it started then the stock bolts to pull it in.

One better have the arm angle right out of the gate. I centered my adjustable Carrera arms and used the angle calculator running around here and it worked perfectly.

I skipped the gluing which I should not have. I can hear the rubber creak over large twisting bumps. This is not good as it mean the rubber is acting as a bearing surface and it will create wear.

Polly bushings are different. They are designed to be a bearing surface.

Maybe Chuck Moreland will see the thread and chime in at some point, but this link describes my understanding of how the rubber bushings are supposed to work.

http://www.elephantracing.com/techtopic/polyurethanefriction.htm

The Neatrix bushings are a little harder than the OEM ones that came out, but I would guess they could deform enough to accomodate the full suspension travel.

The inside of the torsion tube isn't perfectly smooth, so I think the bushings would be torn up and worn out in no time if they were to rotate inside of that. But the tight fit probably keeps it from doing that.

Dave,

You made an interesting choice springing for the ER adjustable arm with stock style bushings instead of the PB bushings.

Can you elaborate?

Also, the Carrera arm is already adjustable, is the change it is easier?

;)

They probably stopped because it was a totally pointless idea. I took one apart - one month & 200 miles or so after install with glue. The glue hadn't held & was just a nasty residue. I greased them like Milt. I inspected them again this summer - after 8K miles - and they are still perfect.

Ian

Porschenut, the project looks great!

Rubber bushings are not supposed to slip. They accomodate suspension movement through deformation, stretching like a ruber band.

If allowed to slip, the rubber begins to wear. Further, slipped bushings attempt to hold the suspension in whatever position it is in (compression, static height, extension). This creates an ever changing corner weight condition, negatively impacting grip.

A non-slipping rubber bushing always attempts to return the suspension to its static position, just like your torsion bars. Corner balance remains true.

We use super glue to secure the ID of rubber spring plate bushings. Applied properly to a freshly plated spring plate, the super glue holds permanently.

In the interest of completeness, the product pictured is not the ASP. It is the QuickChange Spring Plate.

what is the effective spring rate of the rubber twisting?

that's what I'd like to know...

Good question. I went with the Elephant plates for a couple of reasons. First, I like the quick change idea, and I may start to track the car again at some point and this kind of spring plate will make it easy to go back and forth between street and track setups. Secondly, I wanted to make my ride height adjustments as easy as possible as I'll be doing them myself, and these spring plates have a much greater range of adjustment than the factory plates. Raising and lowering is just a turn of an 8mm Allen head bolt. Lastly, I didn't want to deal with removing the old bushings from the stock plates. For all that, it was worth the price of the ER spring plates.

BTW, my Neatrix bushings came with Super glue. I didn't use it due to some reports of it not keeping its bond.

Understand.

But why factory style rubber bushings instead of the Poly Bronz ER bushing?

I went w rubber to.

Because for me, factory rubber can't be beat. They're quiet, comfortable, maintenance free, and inexpensive.

My goal with my suspension rebuild was to return the car to "as delivered" condition. I'm not interested in spending gobs of money on performance improvements that decrease ride comfort.

I'm with Milt - these bushings are too thin and the ID is too big for them to accomodate full suspension travel without slipping.

I measured the following graph with the standard bathroom scale and an angle finder. No torsion bar, stab bar, or shock was attached. To Rwebb's horror, wood pieces were involved. The bushings are stock factory pieces w/ silicone grease on the outside, mostly as corrosion prevention (I read a few horror posts on rusted out torsion tubes).

The graph is bass-ackwards. It's actually 2 runs - 1 from full rebound to where the bushing slips, and one from full jounce to full rebound. They're connected in the middle because that's how XL works.

The bushings slip around 40mm of travel. Having the weight of the car on the bushing would probably allow more travel before slip. Also, the bushing slips very slowly. Quick excursions at the unsprung natural frequency would probably allow 60 or 80 mm of travel before slip. I should make clear that by 40mm travel I mean range, i.e. +20 / -20 mm, not +40mm / -40mm.

I get around 7 N/mm at the wheel.

Before I get crap from the peanut gallery, the number seems high to me. But, it is what it is - anyone can measure theirs easily. I may also have screwed up someplace. If anyone came up with different numbers, I'm interested to compare notes.

Another interesting thing is that (assuming my number is correct) replacing the bushing with a bearing would result in a lower ride rate, equivalent to approx. 2mm thinner torsion bar. This may explain the "bearings ride better' experience many folks have had.

http://forums.pelicanparts.com/uploa...1225644071.jpg

Nice test information by burg. Great job!

I've installed the Neatrix as well and I would recommend these to anyone looking to avoid harshness & looking to maintain a compliant ride. Not to mention they perform well on the track too. The installation is a bit quicker than the polybronze and it's basically a jam-it-in-there-and-don't-worry installation. Superglue will adhere the Neatrix to a properly cleaned spring plate- I tracked my car for 3 years with the Neatrix and they remained bonded. Just need to make sure you allow the glue to dry before installing. And use a synthetic grease on the bushing OD to install it in the torsion bar/spring plate housing. Longer M10 screws are without a doubt the best way to draw-in the spring plate to the housing!

I believe i've still got the old Neatrix bushings (replaced with polygraphite.... :eek: this year) if anybody would like to see their condition after some years of track abuse. They looked quite good

I can understand why Dave porschenut switched to the Elephant QuickChange plates. Torsion bar quick change doesn't seem like something that's utterly important (how often do people change t-bars?), but the ultra-quick height adjustment is what I think is the best about these plates. True, the factory plates from 78-89 are adjustable. Yet their adjustment range and fastening of the factory eccentric and sandwich bolts are a PITA. Chuck's elevator bolt and sandwich lug are the hot setup!

"wood pieces were involved"

we've got to get you some Al tubing, man

I am a fan of the factory style bushings to but seems everytime I say that I get beat up by the church of Polly Bronze. (A great product and resource.)

I applod the easy of adjusting. Also, being able to change out the torsion bars w/o having to wreasel out the bushings is a plus.

However, I had my car corner ballanced an alighned at great expence and I would not even concider messing w ride height once it is set.

And yes, taking off the old rubbers is a bit of work.

I would think if the stock bonded rubber bushings were designed to slip and act as a bearing surfice, when we removed them the races they ride in would be shiny and show ware.

It is possable they jump in there races under extream suspention movement but I do not see them acting like this under normal suspention travel conditions.

Just my belife for what it is worth.

Also, have come question about how an lube one migh put on the rubber might effect them.

Burger, your measures are influenced by the grease you applied. The bushings aren't supposed to be greased. A greased bushing is inclined to slip, that is why you shouldn't grease them.

Further, since you don't have the torsion bar in the bushings will slip more readily. With tbars in and the car on its wheels you have the corner weight squeezing the bushing, helping to hold it stationary.