Let's talk alignment, Shims---Do I need them or Do I not need them? That is the question. Options

[mojorisen914]

Need some advice. What is everyone's input on whether or not I need shims. I removed the arm when I was home last time and there wasn't any there. Do you think I will need some when I take it to the alignment shop the next time I come home?
If so; does anyone have any that would like to depart with them for a fee?

[dr914@autoatlanta.com]

Need some advice. What is everyone's input on whether or not I need shims. I removed the arm when I was home last time and there wasn't any there. Do you think I will need some when I take it to the alignment shop the next time I come home?
If so; does anyone have any that would like to depart with them for a fee?

shims only adjust camber, reducing the negative camber. Toe is adjusted by sliding the arm forwards or backwards. Negative camber can be caused by sagging springs or twisted swing arms. Your alignment shop will measure and be able to tell you if you need shims . They come in 20 30 and 40 each reducing the camber by that much in minutes. (a degree is 60 minutes, stock spec for the rear camber is -30 minutes, some of the racers set it to as much as - 1 degree 30 minutes)

[mojorisen914]

Thanks George.
I need to re-phase my question. If everything was good before I removed the arm; shouldn't it be safe to say that I won't need them now. I did however install the springs and Bilsteins I got from you last year.
Hope this is making sense.

[Dave_Darling]

You changed springs, so you changed ride height. You changed ride height, so you changed camber. So it's not safe to say that things will be the same as they were before.

They may be good enough, though, depending on exactly how low the car is and what kind of camber angles you're looking for.

--DD

[Krieger]

I *think* your question is: Is it safe for me to run no shims?

[Cap'n Krusty]

The answer you want is: No, everything's OK and cheap. The real answer is: You changed stuff, you need to take a selection of shims with you to the alignment shop, even if you have to pay for them like everybody else.

The Cap'n

[davesprinkle]

OK, I'm gonna sorta highjack this thread...

I just had my 914 in for an alignment. Rear camber measured out to roughly -2.25' on each wheel. Thus, to get back to factory specs of 0.5', I'll need roughly 1.75' of adjustment. Referring to Darling Dave's post above, this means I'll need qty 4 #40 shims and qty 1 #20 shim. Am I right?

Speaking as a guy without any rear alignment experience, this seems like a big shim stack -- can I stack up that many shims without any problem?

Finally, where can I buy the shims? The usual suspects?

(BTW, it's remarkable how much more stable the car is now that the front wheels are toed IN, rather than OUT...)

[SirAndy]

Rear camber measured out to roughly -2.25' on each wheel.

That means either your trailing arms are bent or your springs are sagging big time.

Even with no shims at all, you shouldn't get beyond -2 degress of camber ...
(IMG:style_emoticons/default/shades.gif) Andy

[PeeGreen 914]

http://engmanparts.com/alignshims.php

[SirAndy]

BTW, it's remarkable how much more stable the car is now that the front wheels are toed IN, rather than OUT...

That's odd. I usually run a slight toe out in the front and toe in in the rear ...

Makes for very responsive steering, which is the way i like it ...
(IMG:style_emoticons/default/popcorn[1].gif) Andy

[41ghost]

get them at autoatlanta, or anywhere you can, used or new. i had my entire front and rear off the car . put it all back on when ready and aligned it all up myself, broke the engine in 200 miles or so, after cam break in . then i took it into the shop to have it alined on a machine, with a few tweeks it was perfect. so i guess what i'm trying to tell you it's pretty easy to play with, do it yourself, not to be afraid of it . but do get it done right buy yourself or others.

[davesprinkle]

Rear camber measured out to roughly -2.25' on each wheel.

That means either your trailing arms are bent or your springs are sagging big time.

Even with no shims at all, you shouldn't get beyond -2 degress of camber ...
(IMG:style_emoticons/default/shades.gif) Andy

I don't think the arms are bent -- the car's never been hit. I did install 140lb springs, which lowered the rear of the car a bit.

[SirAndy]

I don't think the arms are bent -- the car's never been hit. I did install 140lb springs, which lowered the rear of the car a bit.

Good. Just FYI, the trailing arms usually bend when the driver hits a curb. There does not have to be any damage to the tub for that ...

(IMG:style_emoticons/default/shades.gif) Andy

[markb]

We have a box of them if you need some.

[Dave_Darling]

The front toe-in will make the car more stable, at the expense of less turn-in response.

Negative camber, up to a point, is good for cornering traction. A degree or so will generally not hurt tire wear very noticeably, unless you do have toe-out. You don't have to set it up to the stock 1/2 degree negative.

Balancing front and rear traction is important as well, so you may want some negative camber in the front as well. But unless your front suspension is much stiffer than the rear you usually want less of it in the front than the rear.

--DD

[r_towle]

1/8 inch to 1/4 inch toe in at the front is the correct setting for a street car.
1/8 to 1/4 toe out is good for autox.
Toe out sucks at high speed, like the highway...
It will wander into ruts and you have to pay attention.
Toe in, you can drive with one finger.
Toe in is stock on all cars up front.

Rear..
Toe in is stock...zero toe is a good compromise.
Toe out is aggresive for autox and wears tires out fast in the rear.
When you accelterate, the rear wheels toe out...if you set them at zero toe, you can experience almost 1/4 inch toe out under hard acceleration.

New springs are shorter than the original 70/100 lb springs.
You lowered the car, you increased negative camber.
If you have adjustable rear spring perches, you can tune out some of that...if not, or if you like the new lowered position, you must add shims back in to get less negative camber.

You can get about -1 degree negative camber up front with a stock upper strut perch...a bit more in some cars.

Rich

[mojorisen914]

The answer you want is: No, everything's OK and cheap. The real answer is: You changed stuff, you need to take a selection of shims with you to the alignment shop, even if you have to pay for them like everybody else.

The Cap'n

The answer I want is the Correct answer. After spending the money I've spent on my teener the last year; I doubt the cost of shims will break my bank account.
Yes, I changed the rear springs and shocks/struts, wheel bearings and the list goes on and on but is it possble, depending on the shock setting heighth that shims may not be necessary??? Or, is that against all odds?

[J P Stein]

The answer you want is: No, everything's OK and cheap. The real answer is: You changed stuff, you need to take a selection of shims with you to the alignment shop, even if you have to pay for them like everybody else.

The Cap'n

The answer I want is the Correct answer. After spending the money I've spent on my teener the last year; I doubt the cost of shims will break my bank account.
Yes, I changed the rear springs and shocks/struts, wheel bearings and the list goes on and on but is it possble, depending on the shock setting heighth that shims may not be necessary??? Or, is that against all odds?

It is against all odds. With -.5 deg negative in the rear I have a stack of shims about 3/8 + inches high. In the past with -2 deg I had none on one side and about 2mm on the other.

I find it odd that for an all out AXer I run very close to stock alignment settings.....cept for ride height.

[ChrisFoley]

Rob,
It is possible, however unlikely.

davesprinkle,
I fabricate custom trailing arm brackets that are designed to eliminate about 3/8" worth of shims. These restore camber on lowered cars without requiring excessively long bolts to go through all those shims.

[PeeGreen 914]

That's because of all that rubber you have under there in your light little car (IMG:style_emoticons/default/wink.gif)