I am having alignment problems with my Cayman S. About 3 weeks ago, I took the car to my race shop to get it aligned. We got the camber and toe settings as we wanted on the car; however, as I picked up the car from the shop and drove off, within few miles, I noticed that the alignment was off, feeling as if it was going sideways and the rear toe being quite off.


About a week later, I schedule another time slot with the shop to correct the issue. They found that somehow, rear toe, as suspected, was way off. One side +0.1x and other -0.1x. So, one side had toe in and the other had toe out, hence the side ways feeling. Picked up the car towards the end of the day, I drove off, and the same thing.


Couple of days later, last Friday, I took the car in, stayed there and made sure the process was followed properly. I have to state that my race shop has some of the best techs in the area and they truly now what their doing. Nevertheless, I wanted to make sure everything was done by the book (I have done more than few dozen alignments myself on various cars). When we put the car on the alignment machine, we observed that this third time we had rear toe out/in situation like the previos times. We did the alignment, re-verified by going back and forth between the front and the rear camber/toe adjustments, making sure everything were as symetric as they can by to the 1/100th of a degree and that all bolts were properly torque and so forth. Confident of the process, I drove off..... I can't believe it, THE SAME THING!


So, today, owner of the shop called the manufacturer of the alignment machine and the techs came in, I went down with car and we started to whole process again a 4th time. Between 9:30 am and 6 pm, the car got aligned probably 12-14 times, each time narrowing down the possible issues. And between each alignment, we drove the car on the road for couple miles for the suspension to settle down. Alas, no luck, rear and front toe changes from alignment to alignment, we are not getting consistent numbers at all, and the car is still side ways, much more subtle though at this time.


The only things we have been able to rule out were that the machine is calibrated properly and there are no problems with the software. We aligned and verified a different car on the same machine and the numbers stayed the same to the 1/100th of degree.


So, now I am and they are at a loss; we do not know what the problem might be. If anyone experienced something similar, I would really would like to hear about it, or any information you guys can share would be great.


Some facts:

<ul>2006 Cayman S, with PASM, 18' wheel setup, all stock, 11K mi.[/list]
<ul>Alignment machine is the latest technology dong 8-point measurements, Porsche factory/dealer/Motorsports standard. It is really the most expensive there is and software got updated while I was there.[/list]
<ul>Have not had any crashes, pot holes, or similar potential problems[/list]
<ul>Had alignment in March with perfect results[/list]
<ul>Camber does not change (-1.1 front and -2.2 rear) during the process[/list]
<ul>Wheels are in good condition, no bend or any other damage[/list]
<ul>Inspected bushings, no wear signs[/list]
<ul>Inspected all chassis bolts, no signs of tempering, movement or anything else[/list]

I really appreciate some help, I am at a loss what to even try at this time.


Thank you in advance,


FT

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FT

Tires are all o.k. I suppose? No problems with wheel bolts and they are Porsche's not aftermarket? Shop's torque wrench is working properly? No bad wheel spacers? None of the above make much sense as answers but you are reaching now.

I know Santa Fe, I am at a complete loss. Stock wheels, no spacers, tire pressures adjusted each time, wheel bolts checked each time as well. There are no apparent or obvious problems that we can make sense of it, that is why it is long post to see anyone might have experienced something remotely similar.


I appreciate you taking time to read and respond though, thank you.

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FT

Wheel bearings? something is rotating with the wheel setup for toe to change correct? Let's examine:
<h2 align="justify">Toe-in</h2>
<p align="left">The toe measurement is the difference in the distance between the front of the tires and the back of the tires. It is measured in fractions of an inch in the US and is usually set close to zero which means that the wheels are parallel with each other. Toe-in means that the fronts of the tires are closer to each other than the rears. Toe-out is just the opposite. An incorrect toe-in will cause rapid tire wear to both tires equally. This type of tire wear is called a saw-tooth wear pattern as shown in this illustration.
<p align="left">If the sharp edges of the tread sections are pointing to the center of the car, then there is too much toe-in. If they are pointed to the outside of the car then there is too much toe-out. Toe is always adjustable on the front wheels and on some cars, is also adjustable for the rear wheels.
<h2 align="left"><a name="Toe">Toe</a></h2>
<center>
<p align="left">Like camber, toe will change depending on vehicle speed. As aerodynamic forces change the riding height, the toe setting may change due to the geometry of the steering linkage in relation to the geometry of the suspension. Because of this, specifications are determined for a vehicle that is not moving based on the toe being at zero when the vehicle is at highway speed. In the early days prior to radial tires, extra toe-in was added to compensate for tire drag at highway speed.
<p align="left">On some older alignment machines, toe-in was measured at each wheel by referencing the opposite wheel. This method caused problems with getting the steering wheel straight the first time and necessitated corrective adjustments before the wheel was straight. Newer machines reference the vehicle's centerline by putting instruments on all four wheels.
<h2 align="left"><a name="Toe Out on Turns">Toe Out on Turns</a></h2>
<center>
<p align="left">When you steer a car through a turn, the outside front wheel has to navigate a wider arc then the inside wheel. For this reason, the inside front wheel must steer at a sharper angle than the outside wheel.
<p align="left">Toe-out on turns is measured by the turning angle gauges (turn plates) that are a part of every wheel alignment machine. The readings are either directly on the turn plate or they are measured electronically and displayed on the screen. Wheel alignment specifications will usually provide the measurements for toe-out on turns. They will give an angle for the inside wheel and the outside wheel such as 20&ordm; for the inside wheel and 18&ordm; for the outside wheel. Make sure that the readings are at zero on each side when the wheels are straight ahead, then turn the steering wheel so that the inside wheel is at the inside spec. then check the outside wheel.
<p align="left">The toe-out angles are accomplished by the angle of the steering arm. This arm allows the inside wheel to turn sharper than the outside wheel. The steering arm is either part of the steering knuckle or part of the ball joint and is not adjustable. If there is a problem with the toe-out, it is due to a bent steering arm that must be replaced.
<p align="left">What about your steering linkage? Could something be loose there? Obviously for the settings to change during such a short period of time means that something is slipping, what is it that they are adjusting each time to get Toe back inline? Is it being adjusted further and further each time, or is something slipping and being adjusted back to the proper spec? If something is being adjusted further and further then eventually you run out of room to adjust.
<p align="left">Your car is under warranty, take it to the Porsche dealership and have them align it, then drive it and put it back on their alignment machine, does anything change? If so, if Toe keeps changing and your dealership can't fix it then they'll call in the big tech guns from Porsche to get it solved, continuing to go to an independent shop may not be in your best interests in this case. You may have either a known issue that Porsche can quickly solve, or may have uncovered a new problem which Porsche will want to know about and ultimately fix for you under warranty.
<p align="left">Personally I think its the Fetzer valve... [img]/fckeditor/editor/images/smiley/MWPX/wink_smile.gif[/img]
</center></center>

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I know a little bit about cars and a little bit about alignment but also a little bit about logic. I hear a situation where you are in a closed loop and whatever caused the problem is still present as you try to cure it. I'll bet a third party can align the car successfully. A significant factor is that, so far as I have heard, wheel alignment is not a characteristic Cayman problem. Just an arms-length analysis; good luck.

This won't be cheap, but a new set of tires might be needed. Eleven thousand miles is a lot of miles for these tires. Uneven wear could be causing the problem and of course, you cannot rotate the tires to remedy this. You would probably be getting a new set of tires soon anyway. Assuming that a new set of tires resolves the problem you have isolated the problem, if not, you have a spare set of tires that you'll soon be able to use. The suspension on the Cayman is extremely sensitive and it doesn't take much to throw it off.

FT, I had to take my GT3 in for 4 alignments to get it right. So far the Cayman is fine for what I do with it. My God Man? ...11,000 miles already! whats that 4 sets of Tires? Did anybody check your sway bars? Maybe loosen them for the setup and then readjust to that set up? Just a thought and keep us all posted.

First, thank you all for your responses, I really appreciate it.
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Ken -- Wheel bearings, steering linkage, etc. all checked out fine. As a matter of fact, none of the bolts have any sign of movement, we marked all of the bolts onthe chassis, steering, suspension, camber andtoe. The changes are not consistent and what is more is that the alignment dynamically does NOT change. I am so certain that the machine is at fault but I have not been able to prove it as of yet. I will be taking it to the dealer, may be this afternoon or more likely Monday.
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<p align="left">A significant factor is that, so far as I have heard, wheel alignment is not a characteristic Cayman problem. Just an arms-length analysis; good luck.
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ed1 -- That is what I am trying to rule out, a 'characteristic problem' with the CS or may be PASM. There is possibility that PASM valves may be binding enough to miss lead the alignment machine. I might actually revert back to doiing the alignment myself with strings just out of curiousity.



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This won't be cheap, but a new set of tires might be needed. Eleven thousand miles is a lot of miles for these tires. Uneven wear could be causing the problem and of course, you cannot rotate the tires to remedy this. You would probably be getting a new set of tires soon anyway. Assuming that a new set of tires resolves the problem you have isolated the problem, if not, you have a spare set of tires that you'll soon be able to use. The suspension on the Cayman is extremely sensitive and it doesn't take much to throw it off.



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mpollard -- I thought about the same thing. We did the alignments with two different sets of wheel/tires, same results. That also ruled out wheel run-out possibility as well. Frankly, my second set of tires are have only 35-40% wear (trackwheel/tires)on it now and stock tires have may be 15%. Honestly, my tire wear has been minimal given the conditions that I drive in, which also tells me that the chassis and suspension do not have any misalignment issues and they are as static as it can be. Even during the past 3-4 weeks of having the alignment problems, tire wear show no noticeable uneven wear.
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FT, I had to take my GT3 in for 4 alignments to get it right. So far the Cayman is fine for what I do with it. My God Man? ...11,000 miles already! whats that 4 sets of Tires? Did anybody check your sway bars? Maybe loosen them for the setup and then readjust to that set up? Just a thought and keep us all posted.



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Scott -- welcome back from your trip, I hope it was pleasent, good to hear from you. I cannot stop driving the CS, the Bimmer is collecting dust frankly [img]/fckeditor/editor/images/smiley/MWPX/teeth_smile.gif[/img] As mentioned above, tires are just fine, I bet they'll go another 15K mi. at this wear rate, but I think the track tires will done at the end of the seaon, which is still not bad considering my tire cost has not exceed $600 for whole season; unless of course this alignment issue is not resolved. I might have a huge issue that might cost me quite a bit to identify and fix, cross fingers.
<p align="left">Did you have a similar issue with your GT3 or it was something simpler? What has some logic in my mind, is the overall chassis/suspension stiffness. The stiffer it is, the more binding points. However, springs are very low rate, I think in the low 200s lbs/in., hence static weight at each corner may be changing and not unbinding between alignments and throwing off the machines laser readings. I don't know... I am reaching for some explanation that is going to make sense overall.
<p align="left">And... yes, I personally verified the A/R bars and their bolts as well. The good out of this, I now pretty much how this chassis is put together and few tricks for setup [img]/fckeditor/editor/images/smiley/MWPX/thumbsup.gif[/img]
<p align="left">Again, that you all very much for taking the time to respond to my issue and the discussion you have created. Each bit of information helps. <u>THANK YOU!</u>
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Edited by - FT on 07/28/2006 07:48:47 AM

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FT

<hr width="100%" size="2" />
quote: Camber does not change (-1.1 front and -2.2 rear) during the process

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FT- I just had my alignment re-done to take out the massive understeer the factory seems to dial into these cars - and the alignment specialist at the local dealer was able to get -1.0 camber on the fronts. I was allowed to work with him, and he said any more then that would effect the toe to the point where tire wear in daily driving would be effected. I also think your rear camber is pretty steep, and might be effecting some of the other readings, too. When i talked with a friend of mine at jerry Woods' shop about alignment (and they do some of the best suspension set-ups on the West coast) they said no more than about -.7 to -.9 in the rear, otherwise it starts to effect toe and thrust angle...



Just a thought... I probably have just enough knowledge of this now from my recent experience to be dangerous. If it were me, I'd take it to a dealership and see if they can set everything to stock factory specs and see how the car drives... it it drives ok, then go from there with custom settings... if it doesn't drive ok after they set it, then the problem is in their lap for them to fix under warranty...



brad

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so why did you take it to the race shop in the first place