: Caster Alignment



cts-v ls6
12-11-05, 04:29 PM
Guys,

I printed off the alignment specs for the V off of the FAQ and took them to the "best" 4 wheel alignment shop in Memphis. He said he would get the specs off of his computer and didn't need my copy.I received my car back and it pulled a little to the right. I took it back and the shop blamed the Avon tires, which are cupped, loud and wearing unevenly and went on to say they could get the car to pull straight, but that the V didn't have any caster adjustment! (?) Whatever does he mean? The Avons are unidirectional, so they can't be swapped side to side, only front to rear.

Help!

Thanks,

Jack

04CTSVFLA
12-11-05, 04:39 PM
Cars, in general, from the factory are meant to slightly pull to the right (slightly). The reason they do this is in case a driver falls asleep at the wheel, they do not run into on coming traffic, instead the car veers to the right and onto the shoulder. This is what I read a while ago in some article from a legitimate car stuff source - cant remember which tho.

heavymetals
12-11-05, 04:48 PM
A set of screwed up tires isn't going to make the best alignment job feel or drive right (no pun intended).

Did the guy even compare the #s off your sheet to what his readout was?

Sounds like you got treated kind of bad though.

Dreamin
12-12-05, 12:46 AM
It's rare, but you could have "tire pull"... and the tires could be at fault. Or if your alignment was off (pulled to the right before the alignment)... the tires can wear so they will pull even after the alignment is perfect (pull less but still pull) - but it doesn't sound like your car was pulling before the alignment.

The way to diagnose tire pull is to temporarily swap tires left-to-right (both front and rear) and see if the pull goes away... if it does, it is the tires... if it does not... it's a screwed up alignment. And the unidirectional tread is for getting water out of the way... you'll be fine switching tires and driving for a few miles (as long as it isn't raining).

Here's a detailed procedure to diagnose tire pull:
http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=12

Also, if you get the before and after alignment specs for your car, we can advise further.

cts-v ls6
12-12-05, 06:35 PM
Thanks to everyboby. I'll try changing the tires out side to side and see if that makes a difference. The car pulled arrow straight before, so something's up. I drove the V from Memphis to St. Louis last week and my arm got tired "holding" the steering wheel to the left. I'll advise later.

Thanks,

Jack

BeagleBrains
12-12-05, 09:39 PM
Cars, in general, from the factory are meant to slightly pull to the right (slightly). The reason they do this is in case a driver falls asleep at the wheel, they do not run into on coming traffic, instead the car veers to the right and onto the shoulder. This is what I read a while ago in some article from a legitimate car stuff source - cant remember which tho.
NOT!!!!!!!!!!!!! Alignment controls a natural return to forward, center. Biases of Caster and Camber provide optimum control in curves and when driving straight for the very average driver. Along with that, tire wear is maximized.
I have been going to a very sophisticated alignment shop since I started driving performance cars. The reason this shop is so popular is that he asks what your driving habits and preferences are. From that, he custom tunes the alignment. The best example of his expertise was when we bought an econobox Buick Skyhawk. It ate tires like they were free. He analyzed the wear patterns and also interjected his experience, along with information from real custom alignment shops from around the country. With that, he gave me back a car that tracked very nicely. My tire wear problem proved to be eliminated, after a year of driving with his custom tuned setup. Factory alignment, like most mass produced stuff, is at best a compromise. I prefer a near neutral return to center that suits agressive driving.
I have spent some time investigating driving habits affected by preferences on car alignment. Usually a pull to the side of the road is due to the fact that many roads peak slightly to the center to control drainage, sloping to the outboard edge. Since the US driving pattern is to the right, cars will naturally drift to the right without having to shut your eyes.

ace996
12-12-05, 09:54 PM
IIRC, the V has adjustment for caster....anyone?...anyone?
-ace

L.Sanchez
12-13-05, 01:02 AM
The specs your alignment guy pulled were GM specs that are already uploaded into the computer. If you were trying to put on a slightly custom alignment, he should have taken your paper.

Caster and camber are both adjustable. And usually, one is suseptible to change from the other depending on the type of suspension. An ideal alignment will not pull from one side or the other including under acceleration, deceleration, or just cruising, at least from the factory. Some of us tinker with the Toe too which can usually change that.

And yes, sometimes tires do affect alignment, especially if they are older. But have him recheck the specs on the alignment first.

urbanski
12-13-05, 09:42 AM
this is one instance you may want to visit your dealer for....
dreading dealers as much as any of us, i too visited independent alignment shops around town. Most wouldn't touch my custom wheels, some didn't have specs, not one would take my sheet with how I wanted the job done.

Dealer saw me the next day, set it up as close to my specs as they could. No wheel damage, either. Worth a shot.

04CTSVFLA
12-13-05, 01:35 PM
NOT!!!!!!!!!!!!! Alignment controls a natural return to forward, center. Biases of Caster and Camber provide optimum control in curves and when driving straight for the very average driver. Along with that, tire wear is maximized.
I have been going to a very sophisticated alignment shop since I started driving performance cars. The reason this shop is so popular is that he asks what your driving habits and preferences are. From that, he custom tunes the alignment. The best example of his expertise was when we bought an econobox Buick Skyhawk. It ate tires like they were free. He analyzed the wear patterns and also interjected his experience, along with information from real custom alignment shops from around the country. With that, he gave me back a car that tracked very nicely. My tire wear problem proved to be eliminated, after a year of driving with his custom tuned setup. Factory alignment, like most mass produced stuff, is at best a compromise. I prefer a near neutral return to center that suits agressive driving.
I have spent some time investigating driving habits affected by preferences on car alignment. Usually a pull to the side of the road is due to the fact that many roads peak slightly to the center to control drainage, sloping to the outboard edge. Since the US driving pattern is to the right, cars will naturally drift to the right without having to shut your eyes.

Dude, your wrong. I promise you that if you go test drive, hop in ANY brand new car on any BRAND NEW CAR LOT, and I guarantee it pulls slightly to the right when you release the steering wheel (very slightly, and gradual). While people may go get the alignment changed to center, initially almost all cars (definetly AMERICAN) should pull slightly to the right. As I said before this is a general thing done to prevent drivers falling asleep at the wheel from driving into on coming traffic. I READ THIS IN EITHER CAR AND DRIVER ROAD AND TRACK or some other mag. cts-v ls6's car is probably pulling more than normal per his description, but all cars should have a slight pull to the right very slight when releasing the steering wheel. IT SHOULD NOT HOWEVER BE
arm got tired "holding" the steering wheel to the left THAT BAD.

heavymetals
12-13-05, 01:46 PM
Mine drove straight off the lot.

It is the "crown" in the road that inputs any "bias" into the steering.

On a "flat" road the car should not pull to either side and one shouldn't have to steer the car straight.