MartyZ51

The last 2 track days I started the weekend with a perfect alignment but ended with a toe problem. There is no play in the tie rod ends, the hubs are new with no play, the adjustment bolts on the on the lower A-Arms are tight. I don't see how it could have slipped. Last time a corded the right front tire and now the right front seems to be pointed out. The steering wheel is cocked to the right and I don't remember hitting any bumps?

I can hear a slight knock/grind when I aggressively turn right or left. I attributed it to the lowering bolts I just put in needed grease to slide on the pad in the lower control arm.

I'll take it in this weekend for an alignment and get the details of the adjustments they make. I could mark all the bolts if it happens again.

Is it possible that the rack is slipping? Could the bushings in the front have wear or be an issue? The car only has 25k on it.

Any thoughts?

hungryhippo

What kind of lowering bolts are you using? My front end seemed like it was getting lower after each track day, i thought it was the springs settling, but realized it was the rubber pads of the stock lowering bolts getting smashed and lowering the front end. This is just with stock sized street tires and stock brakes w/ race pads. So maybe your car got lower from damaged lowering bolts and threw your alignment off

Bill Dearborn

You need to get yourself some toe plates, tape measures, and a digital laser level to do quick checks on your alignment at the track.

Bill

MartyZ51

I'm on a ZO6 front spring with an aftermarket bolt of some sort. They were on the springs when I got them. There is only 1/4 of rubber pad on the bottom of them.

Good call out on measuring ride height. It doesn't look lower on one side but it very well could be.

I was totally wishing I had the ability to check alignment at the track. I trailered a total of 5 hours round trip and only got 2 sessions in before the alignment was out.

Is it possible there could be something wrong with the rack?

sperkins

How do you know you started out the weekend with a perfect alignment if you didn't do it yourself. Never ever trust a print out from any shop unless they are well known and reputable.
C5's are very easy to align. With some very basic tools, you can set it yourself and check it when in doubt. It's your tires/money and more importantly your safety on the line.

BTW - not saying it's not possible, but I've never heard of a rack causing your issue. My bet is that it wasn't done right in the first place.
Also, if the right front tire is facing out as you said, the steering wheel would be off to the left when going straight - not to the right as you described.

MartyZ51

Yah I get it about the alignment. The steering wheel was pointed straight until I went out for the third session. Then it was pointed to the right. Hoping it is just a lose bolt...

Bill Dearborn

Could very well be a loose bolt. Several years ago I had the alignment set on my 03Z. Stood there and watched the guy align it. He got everything where I wanted it. Went to my first track event and the car was handling terribly especially on right handers. I got the car back home and started looking at it and the rear wheels didn't look right so I made up a string set up and checked rear toe. Right rear wheel was toed out ~ 3/4 of an inch and the left rear wheel was toed in ~ a half inch so thrust angle was completely off. Took the car back to the shop and this time the manager watched with me and made sure the mechanic really got the cam bolts tight.

Bill

Solofast

Not only tighten the bolts, but mark the excentrics and bolts with nail polish or paint. Put a strip across the excentrics, the bolt and onto the frame. This serves two purposes.

1. If it slips you will know it by just looking at it. It will be obvious that it slipped.

2. You can very quickly put it back to where it was and get on with life without going back to the alignment shop or dragging out the string and or alignment tools.

This trick courtesy of Raftracer who did it on my car when he aligned it way back when and it is still good.

On these cars I'd highly recommend it for the street. It's mandatory for track duty on sticky tires.

0Anthony @ LGMotorsports

Completely agree.

The best way to do it would be to put camber blocks on the car and lock down the lower control arms. You will find the stickier the tire you go, the more it is going to move the arms.....and when camber is effected so is toe.

Vettechris996

+1 to Anthony and Solofast's recommendation. I just marked mine with a sharpie. Make sure you mark all 4 eccentrics up front. You can slip one end of a control arm and not the other which will also cause issues. Its too simple not to do it. When you get sick of dealing with the slipping, a camber kit is a must.

MartyZ51

So the camber kit just takes the eccentrics and replaces them with a square to fit the space n the lower control arm? My understanding is that it doesn't give more camber but instead locks the lower control arm in the full out position?

Is the stock bolt and eccentric a wear item? I ask this because i've been on hoosiers with the same alignment and wheels for several years and never had it move like this.

I'll definitaly mark this one when it's back in alignment.

sperkins

There's a guy in Macon Ga (hint hint) that makes blocks that allow the max camber that the cradle will allow. Most of the local racers are running them. Let me know if you want his contact info.

0Anthony @ LGMotorsports

The problem is, depending on where that bolt is, how easy it is for the tires to 'pound' it out of position. You get into a sticky tire, and start running up on the curbs in the corners and it can very easily knock it out of position.

Using a block there, keeps that control arm where you want it and you then adjust your alignment at the top control arm in the front.

If it goes out of alignment again with the blocks in place...you probably hit something hard and it bent something.

froggy47

The LAST time (forever) I let a shop align my c5z, bubba didn't get the bolts tight & I ruined 4 a6's. Now I have camber plates (no slip) and do my own alignment.

At the very least, put witness marks on all alignment nuts/bolts.

froggy47

There are BOTH types.