front-end camber ?'s

[kmack]

Ok, so here's a stumper:

I had the alignment (toe-in only) checked and fixed (after a complete rebuild) last Wednesday. This weekend I took a trip of almost 600 miles. Car still pulled a little to the left, but it wasn't bad. When I got home last night, I noticed that the outside 3" of tread on the driver's front tire was starting to show cords! Big time wear!

So I took the car back to the alignment shop to have them fix the problem. They checked it all again and said the toe-in was still correct. Now they realize that they cannot adjust the camber on these cars, but they showed me on the machine that the camber on the drivers is out. Too much positive camber.

ok, so here's the start of my questions:

1) I have the stock suspension. New strut cartrigdes, ball joints, tie-rod ends, and T/C rod bushings, stock springs. All the manuals say the camber can not be adjusted. The shop recomended that I go to a frame shop and have them pull the strut tower, but I've already had the car on a frame machine once and it's correct. What can I move or adjust?

2) All the manuals have a "measurent" for the camber but it doesn't make sense to me. They list camber as: " 50' +/- 30' ". Anybody know what this means? And can it be translated into degrees?

3) I know I can slot the holes where the strut mounts to the tower. Are there any ill-effects to doing this only to one side?

4) Another option is the get a camber adjusting kit, either for the top of the strut or on the control arm. Any opinions on either one? Which one would be better in this case? I know MSA now sells a kit the mounts on top of the strut assembly and still uses the stock mounting holes (un-cut). Has anybody tried these?

5) The manuals list a different free-length on the springs from right to left. If I somehow happened to get the 2 reversed, could it cause this type of problem? (as if I can somehow believe the answer to my problem could be that easy!)

Also, the wheels I have on the car are 14 x 7's, with Yokohama S306 (P215/60 R14) tires.

Any other ideas or something I may be missing? I can not drive my car until I get this problem fixed. Please help.....

[hmsports]

One minute it 1/60th of a degree. So, from what you were told, 50' would convert to .83 degree plus or minus 30', or one half of a degree.

What could cause the problem, if the frame is straight, is that the tower is tweaked. If this is the case, you should see some misalignment with the hood. I'm not sure the best way to measure for this. Maybe park on a very level surface and using a bubble level and a protractor, check the angle of the inside of the strut tower with vertical. This may tell you if the left one is tweaked at all. An adjustable strut bar may allow you to pull the towers together, helping things a bit.

I wouldn't spend the money on camber plates. The easiest way would be to slot the current holes. With the strut tower isolator, you should be able to get about 1/2 degree adjustment or so.

I can't find my good manual so I can't give a true reading on what the camber should be, but I would think less than a degree of negative would be best on a stock Z.

Hope you find your problem - I'll be interested in the results.

Rick

[kmack]

One minute it 1/60th of a degree. So, from what you were told, 50' would convert to .83 degree plus or minus 30', or one half of a degree.

Rick

So if the manual says " with standard load, camber .... 30' +/- 30' " then my measurement should be 1/2 a degree +/- 1/2 a degree? Is this positive or negative camber? Is it better to have negative or positive camber? How do I measure it? Just use a straight edge on the outside of the wheel and use a degree wheel?

Oooooh! My head...too many questions....:stupid:

As for slotting the strut tower, I'd like to kind of stay away from that mainly because the other side doesn't need it. Might take away from the resale value later, no? "Why does this side have slotted holes and not the other side?"

Something else I just thought of.... if I did slot the strut tower holes, is there anyway to convert the 1/2 degree into an actual measurement (either inches or mm) of how much the strut needs to move at the top of the tower?

Maybe I just need to get my body dimension sheet out and just measure the damned thing out myself.... I hate having to rely on "shops" to do work. Sometimes it just seems they want to screw you....

[hmsports]

I would also recommend you stay away from slotting just one side... or both for that matter... unless you are planning on auto-crossing or the like. But then you would do it right and get excentric bushings and/or camber plates.

Take the time to do the measurements and try to figure out exactly what is causing the misalignment.

I'm sure that they are stating negative (top part of tire angled inward). Under cornering loads, the body roll would change the camber of the outboard tire to a more vertical angle keeping more tire patch on the road. In road racing, we have anywhere up to -3 degrees or more camber front/rear - depending on the track. Performance driving requires more - check out the rear of most BMWs.

Measure it using a flat board against the rim only if possible so you can avoid tire sidewall deflections/imperfections. Not super critical though. Use a level and protractor again. You can get fairly close. They make some easy to use camber gauges for about $40 - probably not worth your money though.

Glue the protractor to the board (or hold it if you have three hands :classic:) - hold the board against the tire with the protractor aligned vertically and then use a small level - held horizontally to get the angle. Mark a center line on the board to align to level to.

[kmack]

Rick, Do you think one of those angle finders (like what is used in construction, I think I can get one at Sears) would be acurate enough for this?

[hmsports]

You bring up a good point. I've got an angle finder that has a 360 degree scale with a magnetic base that I use when building roll cages. I'm sure that something like that would work perfectly for this.

Harbor Freight has them for sale for $3.99...

[kmack]

Thanks for the help, Rick.

I'm going to track down one of those angle finders this weekend. Maybe by next week I'll be in a better mood to actually start working on the thing.

[kmack]

Ok, for those of you following this thread....

I located an angle finder, better known as an "Automatic Protractor" by Sears. It gives the angle in 1/2 degree increments.

In order to use this, I cut a piece of 1/8" x 3/4" flat-bar just big enough to fit across the wheel rim from edge to edge. (On my wheels I have a nice flat surface right along the bead of the tire which makes for a pretty good measuring surface.) I then took some wire-ties and strapped the angle finder to the flat-bar. Then I found a small bubble level and mounted it above the angle finder so that I know exactly when the bar is vertical, which I need to do in order to get an accurate reading off the angle finder.

I wish I had my friend's digital camera, because this thing looks really "cheesy". :classic:

Anyway, so I took some measurements this evening.....

Passenger, front = 1/2 degree, negative camber

Passenger, rear = 1/2 degree, negative camber

Driver, front = 1 degree, positive camber

Driver, rear = 1/2 degree, negative camber

So according to that, my left front tire is 1-1/2 degrees of camber out from what it is supposed to be.

It has been suggested to me that part of my problem might be in the fact that I'm using Gabriel VST strut inserts (AutoZone special), but that doesn't explain why only one side or only one wheel is out and the rest are correct.

And still continuing on the spring issue, I plan to pull the springs off and measure them, just to make sure they are where they're supposed to be.

I'll keep everyone posted.....

[hmsports]

I know its probably a long shot, but do your front control arms have excentric bushings?

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Here's a few places to check measurements - quickly and easily...

Take a measurement from the front control arm inner bolt heads to the same part on the back of each spindle. Both sides should have the same measurement.

Use a level vertically inside the engine compartment on the strut tower to see if the driver's side is tweaked out (I know I mentioned this one before - just didn't know if you had a chance to check it)

With the car on a level surface, you can measure the loaded spring height - that may give you a quick indication.

Also measure from the bottom of the frame rail to the top of the control arm.

----

Just tossing out some other things...

Have you checked the tension control rods to make sure both sides are set the same - I don't that that could cause any problems other than incorrect toe/caster - at least not 1.5 degrees of a camber difference I'm sure.

I know there's not much chance of the control arm being bent - I'm sure it would stick out like a sore thumb if it was.

[kmack]

Thanks for the ideas, Rick.

I'm going to try and tackle some of this this weekend, but it has to be after the suprise Graduation party for my wife on Saturday.

I'll let ya'll know what I find....

[Graeme Suckling]

All this camber measuring stuff is very interesting but it is essential that you start with a REFERENCE.

By that I mean the car must be on a flat level surface or any readings taken on a per wheel basis may be biassed as per the entire car.

Since the values we are trying to measure are pretty small, it wouldn't be too hard for the car to cancel out the camber on one side and increase the reading on the other, just by simply being on an angle.

I would suggest a spirit level applied to the under side of the engine x-member to check for level.

Then if necessary, a scissor or trolley jack could be used under the low side suspension arm to raise the car to be level.

Hopefully we are only talking a few mm here.

Any camber readings taken at the front will then be relevant side to side.

Similarly for the rear suspension.

All this relies on the fact that SOMETHING has to be straight and undamaged to be a reference.:classic:

I'll be looking for an angle finder tomorrow!

[kmack]

I'm thinking aloud here, but opinions are welcome.

I'm going to make my final measurements (before I change anything) with the car on jack stands on the suspension. Therefore, the suspension will be loaded down with the cars weight.

My reasoning being that I'll be able to spin the wheels and take readings at various points on the wheel to come up with an average. The only way to do that would be to have the car jacked up, but still have the suspension loaded to get an accurate measurement. I can also then guarantee that the car will be level.

This will also make taking measurements of suspension parts (control arm, etc.) easier.

Any reasons why I shouldn't do it this way?