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Discussion Starter #1
Hey folks,

I'm trying to get my camber dialed in, but I keep getting weird results when adding/removing shims.

After the shop's first attempt the front camber was at -1.8L and -1.9R. I thought that was a little higher than I wanted, so I had him add 1 shim to both sides, expecting -1.55L and -1.65R. After doing this I got -1.4L and -1.5R. Odd.

I took it home and after thinking about it I decided to pull 1 shim from each front side. The rear was at -2.3L and -2.1R, so I decided to pull 1 shim from the right expecting to get -2.35.

I brought it back to the shop and they're getting -1.5L and -2.0R in the front. So removing a shim caused the left to change by .1 and the right by .5.

The right rear is at -2.7, for a change of .6 with 1 shim.

My question is, what happened to the .25 degree per shim rule? The actual changes seem to be all over the place. Or are my expectations for the repeatibility of the alignment rig too high?

Thanks!
 

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Are the camber measurements being taken with ballast in the car?
 

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There are two different shim thicknesses I believe. Don't know what they are though. The shop might be mixing them up.

xtn
 

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Discussion Starter #4
I'm sure the latest were with ballast (150#). It's possible the middle readings were without ballast...I'll ask when I pick her up.

I'm certain I removed the 1 mm shim. I can't imagine that the shop would have removed a 3mm shim to make the small adjustment I was asking for.

Thanks,
Tom
 

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I'm sure the latest were with ballast (150#). It's possible the middle readings were without ballast...I'll ask when I pick her up.

I'm certain I removed the 1 mm shim. I can't imagine that the shop would have removed a 3mm shim to make the small adjustment I was asking for.

Thanks,
Tom
Besides the differing shim thickness (I believe there are 1 mm and 3mm shims), beginning with equal static camber (w/o ballast) side to side can result in an approximate .3 to .4 degree change side-to-side with ballast, so it's important to compare apples to apples. For example, when we weight the drivers side only (for corner weighting), we find that the driver's side front loses ~.1 to .2 degree of negative and the passenger's side gains ~.2 of a degree of negative.
 

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It's probably reasonable to expect that kind of measurement-to-measurement "noise" in the equipment at the shop you are using. Equipment set-up is key, so making geometry changes without changing that set up (e.g., toe settings) is more likely to give you a true measurement of change than you'll get when the set-up has to be re-done for a new measurement.
 

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Discussion Starter #7
Hmmm...lack of ballast on the middle settings could explain this. Hopefully the tech is there when I pick her up.

Thanks everyone.

Tom
 

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i've never seen a car that will go to -1.8 in the front without milling the arms. carl
 

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Discussion Starter #9
The arms are milled...took 5mm off in my company's shop. Should have come from the factory that way.
 

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Discussion Starter #10 (Edited)
Hey Jack,

What effect, if any, have you noticed of ballast on rear camber?

Thanks!
Tom
 
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