A few questions on allignment and corner weighting???

[Cobra4B]

First of all what are the stock camber specs of a Z06?

If I make mine 1.5 degrees front and rear (I've heard this is good for the track) will I wear out my tires faster, or is this a good balance for improved handling and decent tire wear? Whats a good alignmet spec for track and the street?

Is corner weighting worth it for a weekend hobby racer? How much would it cost? Where could I get it done in eastern Virginia?

[Cobra4B]

ttt anyone?

[No Doubt]

Front
-1.0 to -1.5 deg Camber
As much +Caster as you can get
Neutral Toe

Rear:
-1.0 deg. Camber
1/8" toe IN each side, 1/4" total toe IN

More advanced Alignment:
Front:
-1.5 to -2.0 degrees Camber (as much as you can get)
As much + Caster as you can get without sacrificing Camber
Neutral to 1/16" toe OUT each side 1/8" total Max.

Rear:
-1.0 to -1.5 degrees Camber
1/8" to 1/4" toe IN each side, 1/2" total max.

Service Manual Specs:

Front Individual Toe: +0.04 degree +/- 0.10 degree

Front Sum Toe: +0.08 degree +/- 0.20 degree

Front Individual Caster: +6.9 degree +/- 0.50 degree

Front Cross Caster: within +/- 0.25 degree

Front Individual Camber: -0.70 degree +/-0.50 degree

Front Cross Camber: within +/-0.25 degree

Rear Individual Toe: -0.01 degree +/- 0.10 degree

Rear Sum Toe: -0.02 degree +/- 0.20 degree

Rear Individual Camber: -0.68 degree +/- 0.50 degree

Rear Cross Camber: within +/- 0.50 degree

Yes, corner weighing is a good idea. Ideally you want to be sitting in the car or have an equivalent amount of weight there. This way any preloads on the swaybars can be removed and you can adjust corner heights to get the cross weights as close to 50% as possible. Without adding or moving weight to/in the car that is the best you can do.

[Subdriver]

Specs:
Front Individual Toe: +0.04 degree +/- 0.10 degree
Front Sum Toe: +0.08 degree +/- 0.20 degree
Front Individual Caster: +6.9 degree +/- 0.50 degree
Front Cross Caster: within +/- 0.25 degree
Front Individual Camber: -0.70 degree +/-0.50 degree
Front Cross Camber: within +/-0.25 degree
Rear Individual Toe: -0.01 degree +/- 0.10 degree
Rear Sum Toe: -0.02 degree +/- 0.20 degree
Rear Individual Camber: -0.68 degree +/- 0.50 degree
Rear Cross Camber: within +/- 0.50 degree

Camber:
-1.5 front will work well on the track, but expect accelerated front tire wear. Everything is a trade off.
There is no perfect alignment for the track and the street. You either compromise wear for handling or visa versa.
-1.5 rear is probably unachievable without T1 camber plates. The most negative I could get stock was about -1.1 driver's side and passenger side set to match.

Here is a suggestion for a compromise track/street setup:
Camber: -1.25 front, -1.0 rear (almost within stock limits)
Caster: max positive, matched side to side
Toe: 0.1 front, -0.1 rear

To improve handling at the cost of tire wear, use more negative camber, slight toe out in front, slight toe in rear.

I wouldn't worry about corner weighting for the occasional weekend DE. I would ensure the front of the car is lower than the rear by checking the frame heights right behind the front wheels and right in front of the rear wheels. This will prevent, or minimize, high speed lift.

If you did want a professional race alignment, the nearest shops I am aware of are in Philly, Atl, or Florida. There are probably some near you, but I'm just not familiar with them.

[No Doubt]

-1.5 rear is probably unachievable without T1 camber plates. The most negative I could get stock was about -1.1 driver's side and passenger side set to match.

Yes. Hard to get more than -1.1 rear at stock ride height or without camber plates. I use -1.5 rear but I have coilovers.

I should add that if you can get over -1.3 rear you may be too low and made this possible by changing the camber curve. In which case without a shorter shock body you also run the risk of bottoming out.

[Cobra4B]

Thanks fellas... I'll have to get the ride height right and get it alligned perfectly.

[Redshift]

I just installed a Hardbar camber kit which is supposed to set front camber at -1.8 and rear at -1.4. The only variable left to worry about is toe, which I'll have the alignment shop take care of. I will have them check the camber as well, just to see how it looks, but it's not adjustable now.

The kit installs easily, just takes time to line up the A-arms and the chassis. Took me a few hours while taking my time and doing wheels/tires and brake pads at the same time. Of course I'm also still slightly injured from last October, and it was cold in there, so I'm sure that didn't help either

Now if only I could get data on the crash-worthiness of the built-in "hoop" on the C5/Z06, I might be able to lose my 80lb rollbar and use the new Hardbar 3lb carbon fiber harness bar instead!

[No Doubt]

The problem with a hoop alone is they afford little to no crush protection for the front windshield frame and not much on the sides above the doors either. In the event of a crash or severe rollover they provide some protection but if the roof forward of the hoop crushes you may end up trapped inside with no way to get out.

It's for this reason as well as no side impact protection they are not legal for any true racing.

A harness bar, although they do allow one to be belted in well, affording better car control and therefore some degree of safety are generally not designed for crash worthiness. Their purpose is to hold one in place while autocrossing, etc. where true crash protection is not needed.

[Redshift]

Agreed. But I am not racing, only doing driving events and some instructing. I have a four point rollbar right now, but this also does not give me any side impact protection nor windshield frame protection. So if that is the case, and I'm not willing to get a cage welded in, my alternative is the harness bar. If the rollbar is not giving me any extra rollover protection, I may as well save 80lb and go with the harness bar, right?

Cobra4B, I'm sorry for partially hijacking this thread.

[No Doubt]

Not trying to start anything here but a 4 point rollbar (hoop) still offers more protection than a harness bar alone, imo. Granted they weigh more but it's a tradeoff for the sake of additional protection.

I should add they are also required for SCCA Solo I (time trials).

[Redshift]

Originally posted by No Doubt
Not trying to start anything here but a 4 point rollbar (hoop) still offers more protection than a harness bar alone, imo. Granted they weigh more but it's a tradeoff for the sake of additional protection.

That's why I have one, but if I saw some data on the crash testing done on the hoop built in to the car, I may be inclined to change my opinion on the topic.

For now, I'm sticking with my rollbar.

[No Doubt]

You have a nice setup, no question. It's just an interesting debate. The fact is a production street car, and that is what we're talking about here, meets DOT safety standards for street use. They are not required to meet the safety standards of a sanctioning body for racing purposes. However, when you are on a track attaining speeds far greater than any legal highway speed you have entered a realm that is usually beyond the DOT crash worthiness standards for street use at legal street speeds. Combine this with the fact you are attaining these high speeds lap after lap and the risk is multiplied further.

It would be great if no additional protection were needed or required then the added weight, cost and complexity wouldn't be a factor. Unfortunately that is not possible so whatever you do is a compromise of those three factors.

[Cobra4B]

Hey hijack away... I got the information I needed!

[Porsche Killer]

One of the best threads I have read in weeks. Good stuff guys. I am printing this one out for future reference. My alignment man will love this one.