Bustadouglass

Im currently in the process of researching and building my 951 for Drift/Time Attack. From what I understand the ball joints are the weekest link of the suspension set up.

So I have a few questions reguarding this...

First - When they do break, do they typically show wear before hand or do they tend to just go catastrophic? Also when they give, what else tends to get taken out with it? I ask because I dont mind replacing them from time to time if I can catch them before they go.

Second - A local Porsche Performance Mechanic told me If I plan on tracking the car I have NO OPTION but to convert the ball joint setup over to another setup. I dont remember what exactly he said the set up was?

Third - Is there any way of reinforcing them to make them stronger? I say just because it would be cheaper than the above option.

Thanks!

a4944

What year is your car? I have a 1986 944 Turbo and the aluminum control arms and the balljoints were nothing but problems. I went through some expensive tires because new ball joints went bad after a couple of track events.

I ended up going with reinforced steel control arms from the normal 944. You can do a search on steel control arms to get info. They only fit on a 1986 though. This is an inexpensive solution. You can also go with after market control arms but these will be expensive. There are balljoint kits for the stock aluminum arms but they did not work well for me. Perhaps my arms were worn.

If I got another 951, the stock aluminum control arms would be one of the first things I replace for a track car.

Thanks,
Mark

Bustadouglass

Just found this. Whats your opinions?

http://www.rennbay.com/ball-joint-re...kits-c-30.html

Bustadouglass

Mine is an 87'. From what I hear the sus. is completely different between 86 and 87. I beleive it is the same as 968 setup.

Trucho-951

Do you remember where you got the re-enforced steel control arms? I have an 86 951 and have been thinking of doing that also. Thanks

Ski

If you are going to race, and I mean full out - get this trophy or that, then you need to go to Charlie Arms, Racers Edge arms, LR has some arms and one other company(blassak ?). Most of these have 19mm ball joint pins for a reason. You will have to remove your spindles and have the ball jt receptacle drilled/machined for 19mm.

Bustadouglass

The car is (eventually) gonna be a Race Only built car. But for the next 6 months or so its a daily driver/track car.

Take a look at the 19mm setup on that Rennbay.com link a few posts up. Is that what your talkin bout of not can you send me a link?

streckfu's

That's about as far as I got.

951TurboEuroSpec

I have an 86 and had the steel arms seam welded and installed with urathane bushings ment for a rabbit, The rabbit bushings are built better then the weltmeister ones as they have the steel sleeve on the front of the control arm bushing.
Here is a sample of a steel arm seam welded and boxed
hpe these help..

i was told some early 87's could have had the early offset not sure how tru that is..

Bustadouglass

Ill have to get my car in the air this weekend and see exactly what I got. How can I tell if i have the pre or post 87' set up?

951TurboEuroSpec- I bet that really reinforces the arms, but that still would leave me w/ a weak ball joint which I hear love to give out specially if you car is lowered.

Oh yeah! I NEED to replace my lower control arm bushings. Where can I find them for a good price? and can I get some upgrades w/ some sort of full bushing kit?

Bill

Issues I am aware of with the control arms/ball joints:

1. JOINT FAILURE - The ball joint socket in the aluminum arm has a plastic cup that the ball joint rides on. When a boot fails and the joint lubricant dries (no zert fitting in the factory setup) the cup desintegrates. When the you loose the cup, the ball has too much clearance and moves in the arm socket. Rennbay makes a replacement cup, but if this is ignored for too long, the aluminum ovals and the whole arm must be replaced. Porsche does not offer a replacement cup, per Porsche, you must replace the entire arm ($800 approx for pair) when the joint fails.

2. BUSHING FAILURE - Over time the rubber bushings fail. Porsche does not offer replacement bushings. Porsche wants you to "replace". Aftermarket bushings are available and vary in price. Spherical bearings, best and most expensive, Polyurithane, cheap but harsh and squeek, Rubber not available.

3. ARM FAILURE - The arms are designed to operate (up and down motion) in a limited plane. To improve handling, many lower the cars ride height. To lower the vehicle ecentually the aluminum arm is raised, thus dropping the vehicle. When the arm is raised, the ball joint no longer is centered in the alum arm socket. If lowered too much the ball joint will actually hit the outside of the alum arm socket. This over time, works like pulling a crow bar on the end of the alum arm. Eventually people have had the end of the alum arm (where the ball joint is located) snap clean off.

So to summorize, Porsche says "replace, do not rebuild". Rebuild kits are available for cheap. But I have heard, only rebuild if the arm is checked for stress cracks (x-ray, magnuflux, ?) because of the issues above. Do not lower car unless proper geometry is restored. Buy Porsche arms for $800 (approx) and have same above issues, or buy aftermarket arms (charlie, racers edge, etc) for $1,600 (approx) and eliminate the above issues.

baldheadracing

More than you ever wanted to know (and he makes/modifies/re-builds as well):

http://www.blaszakprecision.com/Control_Arms.html

shiners780

I just installed those on my car, the best bang for the buck IMO. ~ $1475 includes tubular steel arms, easily removable/replaceable balljoints, spherical bearings front and rear, and solid billet aluminum caster blocks.

Bustadouglass

YUMMY! now i just have to sell a kidney. Damn!t

Those look like they could be fabbed pretty easily. Not saying I WOULD but COULD... hmmm...

baldheadracing

People have tried. It isn't as easy as it looks to get the arm at a reasonable weight while retaining strength. Also, they're PCA stock class club race legal, etc. Price varies if you want the caster blocks or not.

Markus also sells re-inforced steel arms for both early and late offset for folks on a budget. He also tests and re-builds stock arms for non-track non-modified cars.

(Yes, his shop does the work on my car. I have stock arms due to class rules, and a set of FABCAR's from a long time ago, so I haven't personally used these.)