So I went to have my C6Z carbon edition aligned for an HPDE. I run on 18" CCW's wrapped in Conti slicks. The eccentrics were maxed out on the left side sooner than the right side, so the left side became the limiting factor in how aggressive the alignment (-camber) could be set. The front left would only go to -1.7, while the front right went to -2.7. In the rear, the left rear only would go to -1.4 while the right rear went to -1.7... Odd I felt.

So, camber was limited to -1.7 front & -1.4 rear. I know that if I were to remove washers from the upper control arms that I could have increased the -camber in both the front and the rear, but there was not time for this.

Outside of camber kits, my question is as follows. How much does each washer removed add to the (-) camber at that corner? And once the washer is removed, assuming 1/corner would get me to -2.5 front & -1.7 rear, would I be able to get back to stock specs leaving the washers out??

My plan is to leave it at this more aggressive alignment until mid October the latest, then return to a stock alignment. I'm looking to do 3-4 HPDE days by then. I average about 600-700 miles/month driven. I don't think I'd prematurely wear the street tires much at that amount of miles driven.

Thanks!

Ron

PS, is it 'eccentrics' or 'concentrics'? LOL

 

-.5 per washer is what I found on here.

 

If you wanted to be **** like some of us, you could loosen the nuts on the cradle and take a deadblow and move it over a bit?

Factory washers that I cant find extras of are "approx." .5* each. Vansteel's in the camber kit are about 1/4* and I use hardened washers that allow 1-2/10*.

Repeatability for changing back and fourth to street settings is easy with a camber kit, bit more difficult with the stock wonkey eccentrics.

Could dial to say 2.8* with 1 or no washers then add 3 in for street. I do like stud kits as running bolts in and out of the aluminum frame is asking for problems down the road.

 

I was wondering if I could remove a washer (or 2??), get a track alignment, leave the washer(s) out, and be able to return the alignment to street specs sans the washer(s).
Does anyone know if this would be possible?

Ron

 

I used to do that back when I cared about having a street alignment on my C6Z. You'll need to reset the toe with each change though. Get a set of toe plates and I believe it's a 22mm wrench. Some folks like to count turns but I inevitably would screw that up.

On my C7Z I'm just running full time on the track alignment. I don't think the added camber will have an appreciable effect on tire wear considering everything else.

 

Yes, I know I'd have to reset the toe. What I'm wondering if I can avoid is replacing the washers every year.

So you were able to return to street specs with the washer(s) out without issue?
Do you remember how many washers front/rear had to come out? If I remember, there's only 1-2/corner in the rear to begin with, and 4/corner in the fronts?

If you're track alignment is aggressive/for a slick tire, you WILL prematurely wear & ruin the inner part of the tires if you drive say more than 7,000 miles/year... it may take 2+ years, but it likely WILL happen.

Ron

 

As others have said it's ~ .5 degrees per washer and I was adding/removing 2 as I recall. It really depends on how tame you want your street alignment and how aggressive your track alignment. I do have a Pfadt camber kit on my C6Z.

 

On my C7 Z51, which we user mainly for Autocross.....
(we do drive to/from the events... 25 miles each way)

I had originally set my alignment:
-1.8 front camber, 1/16" out front toe, left caster alone (don't remember what it was... maybe 7 ish ?
-1.2 rear camber, zero rear toe
I couldn't get any more camber into the front or back.
And I lowered it on the stock bolts (about 1/2" to 5/8")
Running on OEM Z51 wheels, but I installed Toyo R888 265/35/19 and 285/35/20 tires.
I also installed LG Motorsports G7 sway bars and end links.
So now we have no side to side sway.
This was a good setup....

But, I wanted wider wheels and tires.
So I got 19x10 fronts (56 mm offset), and 20x11 rears (79 mm offset).
I then installed Toyo R888 295/30/19 and 315/30/20.
But now grip was an issue (understeer).
Also, the tires rubbed on the fender lips... didn't hurt the fenders,
but sure did take a bit of the tire edge off... nothing dramatic.
In fact, this only happened on the drive to the race site.
We had no rub during the event (7 runs each),
and no rub on the drive home. So I figure we removed just a smidgeon
of rubber from the tire edge during highway driving... you know, bumps and
undulations in the highway.

So yesterday I played with a few things...
To get more camber, I removed all the washers... front and back.
There are 2 washers for each mounting bolt... they are each 2.5mm thick,
so we achieved an inward movement of the upper control arms of 5 mm.
Of course, this also moved the top of the tires inward that much too.
(to get away from the fender lip).
I then changed the camber to -2.2, with 1/8" toe out,
and changed the caster to 9 deg each side.
The rears were set to -1.8 and 1/16" toe out each.

I also extended the front way bar end links by about 5/8",
to try to loosen the front stiffness up a bit.

We'll see how this works on Saturday.

The C7 is a great machine.

 

Def stud kit.

 

Washer Smosher - 1 mm = 0.200 degrees of camber

OR

A .050 shim = 0.254 degrees of camber

A .075 shim = 0.380 degrees of camber

A .100 shim = 0.500 degrees of camber

 

Thank you

 

seems you're getting more serious about the track Ron -- when is your next visit to NJMP. I have to schedule something ...

 

Not any more serious, just trying to get the alignment correct..
I went to lightning yesterday! It was a low car count.

 

Anyone know what ride height on C5Z will achieve

-2.7F/-1.8R with factory bolts and camber adjustments?

 

Do they sell the shims as 'U' shape for a C6Z, so I wouldn't have to remove the bolts. Instead, I could just loosen and add/remove shims.

Ron

 

McMaster-Carr, Type 18-8 Stainless Slotted Shim with Tab, Trade Size AA, 1 1/2" X 1 1/2" from 0.005 to 0.250 work on the C5 and C6.

 

I got these, they even have the thickness printed on the shim, high quality.

 

Varies from car to car, but I can't get -1.8 rear with any ride height FWIW. My rear camber with ride height around 5" at the rear jack puck location allows about -1.5 degrees max in the rear.

In the front, though, I can get about -3.5 degrees.

 

Based on the specs in my lead post, I'd only need shims for the left side. Is it wise to do that??

 

I don't believe the cradles move side to side. The passenger side does allow fore/arft movement which can "twist" the cradle so to speak, but nothing that can move side to side....unless you take those pins and remove them or shave them down a bit in size.