ZZ42Fast

iTrader: (2)

Now the Alstons are welded in and the BMR is in, good time to change my tires and get everything aligned. Up till not the car always tracked straight but the steering wheel was always left hand down 1/8 turn.

The drivers side strut mount was all the way in towards the motor before having the alignment looked at today.

They moved the drivers side strut to about half way (so back toward the fender) and they moved the passenger side strut all the way towards the motor!! This was the correct camber and so from there on they did the rest of the alignment.

Driving home it does feel more responsive.. BUT the steering wheel now pulls to the right(passenger side)!! Not badly but enough to annoy me a little.

Question is why and should I just loosen the 3 bolts on the passenger side and move that strut to half way?

Any advice really welcome.

hellz_wings

iTrader: (2)

I believe if you did that then you would screw up your alignment and you would increase positive camber by moving the strut outwards towards the fender... Did they give you a printout of what your specs before/after were?

//<86TA>\\

iTrader: (14)

have you tried taking the car back and have them redo the alignment? Do this before you start moving things yourself, then you will have to pay them to do it again.

ZZ42Fast

iTrader: (2)

The thing is the alignment is correct- I watched the readings. So with correct alignment it pulls slightly. Just not sure what to do.

Guest

Ok, so then what are the specs you have

ZZ42Fast

iTrader: (2)

I went with the specs from "The Camaro Performance Handbook" by David Shelby.

Caster- 4-1/2 degrees positive
Camber- 1/2 degree negative

Not sure on toe...think we went neutral.

I'm using 16" IROC rims. Is it usual to have correct camber but one of the strut tops moved all the way to the motor? If I need to adjust again then there is no more calibration left.?

Guest

You are not listening to the question. You answered what you went for, but what were the final result specs- the printout. You said you were looking at the alignment screen when he did it- was that before he locked things down or afterwards because just because you saw the readings you want, they will change when you turn the bolts and tighten things and then resettle the chassis. The printout will give the EXACT final results.

I you do not have this, the ONLY answer anyone can give you is to go get a professional alignment with a printout sheet. Otherwise, no one can possibly help you if you fail to answer our questions. Without this info you are wasting peoples time even asking this how to correct what you do not even know where you are at yourself.

And to add tt he point, your car will oull to the right if you set your caster equal on both sides- that was a bad call, that is for road race use only, and not intended for any kind of street use where all roads pretty much are designed with a crowned center for water runoff.

ZZ42Fast

iTrader: (2)

Hi Vetruck,

Thanks for taking the time out to help me, I know I'm coming across as a newbie but never done the alignment thing before. I wonder if some of it has to do with the fact we drive on the other side?

Anyway- the specs I gave the were the results I got. They have a state-of-the-art 3d alignment system and measures to withing 1/100th of an inch.

What is the easiset way to get the car straight and not pulling right. Is it a camber thing or just toe?
Thanks again

hellz_wings

iTrader: (2)

What Vetruck said about the caster... Usually to correct for the crown in the road, cars should be aligned with 0.5 degrees more positive on the passenger side of the car, since you're in England, it might be different I don't know how the roads are over there but in North America that's what is the best way to do it... Perhaps since you drive on the opposite side of the road, setting the caster 0.5 degrees more positive on the DRIVER side might be the best setting?

Also, here's some food for thought.. Maybe the alignment didn't screw up the steering? It is possible that maybe something is wrong elsewhere... I don't know how recent your steering system is but I know for a fact that if it's stock there's a good chance something might need to be replaced (Ex: idler arm, centerlink, tie rod, etc.)

As for the strut mounts not being equal on both sides... That is going to happen as our cars are old and they won't be exactly equal on both sides.. I know mine aren't.. They are far apart, probably similar to yours... As long as you dial in the right camber it doesn't matter if they're not at the same place on either side.

ZZ42Fast

iTrader: (2)

Thanks hellz- that is some top notch advice. I reckon a 0.5" driver side positive camber will sort it out.... that should offest the pull to the right in theory

hellz_wings

iTrader: (2)

No, setting camber differently will cause problems, it ust be set equal on both sides... Setting the CASTER to 0.5 more positive on the right side on north american roads will correct for the crown in the road.

Perhaps I was not clear in my last post but setting the CASTER 0.5 more positive on the driver's side is 'just a theory'. I have never been to England before I don't know how the roads are made over there so you would have to do some research about that perhaps ask the alignment tech guy i'm sure he would know something like that... Bring it up to him and see what he says, but don't just set it to 0.5 degrees positive on the driver's side before we know you need to do that. In theory it makes sense but I'm not 100% sure that's what is needed here.

I hope that helps and you can solve this.
Later,
-Marc

Guest

hellz_wings

iTrader: (2)

Actually, you should thank Vetruck, i got most of that info from his posts. He seems to know quite a bit about 3rd gen suspensions lol

skinny z

I don't wish to hijack a thread however there seems to be some positive information being exchanged here so I'll ask my question again.
It relates to excessive tire wear on the outside portion of the front tire tread. Absolutely everything including a-arm bushings, strut mounts, drop springs and all linkages had been replaced. Had an alignment done at a very reputable shop but still had excessive tire wear.
In investigating, I learned that 3rd gens can barely get enough negative camber with OEM style replacement parts. I also read that using lowering springs makes the situatuion worse (although that appears to fly on the face of conventional theory). Add to that an aggresive driving style ( I like freeway on ramps and off ramps! ) and worn tires are what I get.
I've purchsed a set of Spohn strut mounts that provide additional adjustment for negative camber. Hopefully this problem won't repeat itself when the new car goes together this spring.
Somewher here, I've read about alignment specs that differ from the shop manual values.
I'd be happy if anyone else can chime in on this.

SDIF

What size tire do you have?

What pressure do you run?

Where is the toe set?

Where is the camber set?

skinny z

245/50/16
32 psi
+.15
+1.0
All specs right out of the GM manual.

SDIF

I would try bumping up the front tires to 36 psi and the rears to 34 psi. I ran this combo on an all stock 91 z28 to balance the handling and help cure a push. This will help the front tire life too. I ran this on Gaterbacks to improve tire life.

When the car is driven strait, is the steering wheel centered? If not the geometry was not squared when aligned and this can cause problems. The car can always be toed regardless of where the steering wheel is positioned, but you cheat yourself out of the ackerman engineered into the geometry.

Center the steering wheel and make sure the tires are dead nuts strait.

It sounds like a condition of not enough camber and too much toe. Can you get any more camber out of the adjustments? Can you double check the toe.

I am leaning toward too much toe in. I doubt that you can drive the car hard enough to roll it over on the outer edge of the tire on the street. The tire will usually wash out and slip before this happens unless you have really good clean roads.

All of what I said may be wrong for you car, but is based on my personal experience which may differ from that of others.

Good Luck

built91Z28

I'm a suspension tech at a dealership and do alignments all the time so maybe I can help. First, its ok that the strut mounts are not perfectly even. Mine arent either. Second, if you move the strut yourself, your alignment will be out and I promise you the steering wheel will be crooked. If you adjust the camber or caster, it will change the toe as well. Thats why when you do an alignment, you adjust the camber/caster first, then the toe. Third, before you think its the alignment, rotate your front tires side to side. I've had it happen before where a car will drive straight, then I do an alignment and it pulls. Rotate the tires and then it pulls the other way. I'm not saying its not a problem with the alignment, but it could be a tire pull.

ZZ42Fast

iTrader: (2)

Thanks, I have just had 4 new tyres though so don't think that will cure it.. Before the alignment the steering wheel was to the left but the car didn't pull. Now the wheel is to the right and pulls to the right...

RBob

iTrader: (1)

If the pull is from road crown then an additional 1/2 degree of caster on the left side will help (left when sitting in the car). On this side of the pond and on the other side of the road, we usually put the additional caster on the right side to compensate for road crown.

I say usually, since where I am the road crown is so hap-hazard the car is better with a square alignment.

RBob.

RBob

iTrader: (1)

Spirited driving on stock specs will wear the outside edges. Change the camber to 1/4 to 1/3 degree negative. That will even out the wear across the face of the tire.

RBob.

Guest

Yep. To quote and elaborate on this third point- That is call tire stagger. On rear wheel can have a larger circumference that the other. That circumference difference on rear drive wheels will make a car favor the larger of the to and drive the car inside of that wheel. If its larger on the right, the car will reach left on throttle, and visa versa.

Take a peice of string (we use small specific made tire stagger tape measures if you have one that is long enough in you kitchen drawer) and measure the circuference of the same portion of tread on each tire checking its circumference to the 1/16th inch.

skinny z

Thanks for that. I understand the Spohn strut mounts permit camber adjustment beyond what the OEM parts allow. ( IIRC I'm at or near the negative camber limit with the stock setup.)
And thanks to ZZ42Fast for letting me borrow his thread.

captainchadl

question when the final camber is the tires on the pavement correct or is the final measurement while the car is off the ground? So while my car is firmly sitting on all fours the camber should be negative .5 is that correct. And is taking the measurement the same when doing caster and toe?

85irocinjected

Yes, when your car is on the ground with full weight held by the tires thats when you get your final measurement. Same for the other measurements as well, suspension must be fully loaded to get accurate alignment measurements.