$100 for a "good" 4 wheel alignment job seems like a deal to me. I would gladly pay it, if I could find someone good in my area.

Michael

 

I just PM'd you with the name, address and ph. #'s. Didn't want to post contact info since he's not a "supporting vendor".

 

You guys are right about new cars getting the "Drive By" alignment at the factory. Actually that is one of the reasons that the factory specs are so broad. I swear that if the bolts will fit through the holes, it is within factory specs.

When I do an alignment on a C5 or C6, and I do over 150 Corvette alignments each year, I get the caster exactly the same on both sides and go very conservative on Camber with run-flats (z51 or not makes no difference), set the front for 1/8" total toe in, set the rear camber a bit more upright (about 1/4 degree less negitive) than the front and zero toe in the rear. If you do that these cars drive as straight as an arrows flight (provided the cross weight is pretty close). Out of all the cars that I align, I would say that less than three each year are close enough to say "there is no need to align".
When you figure the value of a great handling car and the cost of a new set of tires, a good alignment is money well spent.

 

Mark,

You toe the front IN? Just curious if I read right. Is this primarily for a street setup?

Thanks.

 

IMHO For a street set up, for most road race setups and for Drag racing, you want a slight bit of static toe in on the front of the car. As the car rolls and under braking, bushing compliance and rolling resistance causes the front wheels to toe out. This creates drag and an unstable platform. For Auto-x alot of drivers prefer toe out on the front as it makes the car more darty and causes it to turn down quicker. At high speed it makes the car unstable as the front end hunts especially when one front tire hits a bump that the other misses. In the old days when suspensions lacked Ackerman (toe out in turns) you would put static toe out so that they would turn correctly. The C5 & C6 has plenty of Ackerman designed into the front end for everything but auto-x. Now on a race car (nextel cup or IRL...) you will do anything to keep from having toe in because at super high turn entry speeds, the car will push, but at our legal speeds in normal driving and even track days it is a non issue.

Now the C5 & 6 will toe in under really hard braking due to bump steer, but at the same time they will toe out due to bushing compliance, so the net change under braking is minimal.

So in that regard, I agree with GM and put in just a touch of toe in on the front wheels.

 

I need to thank you for bringing this up. These cars eat tires very quickly if they are out of alignment. I have 3000+ miles on my roadster and forgot all about it. Monday it is going in to the dealer. He bought a $90,000 alignment machine AFTER my car was delivered. During a wonderful open house last thursday at his dealership I made the appointment with the service manager. He said yes he expected the alignment was way off.
This forum really has help me enjoy my roadster even more that I might have with out it. Thanks to everyone who participates!

 

I have to get my C5 aligned every year... No other car I owed went out of alignment so fast.

 

Probably due to the eccentrics slipping.

Next time you get an alignment mark EVERYTHING with a magic marker. The front and rear eccentrics to the frame, as well as the tie rod (the part that rotates to the shaft).

Very easy to see if anything has shifted, and if you're so inclined, you can return it to it's original setting with reasonable accuracy.

 

Cool thanks for the info. I didn't feel any instability at speed with toe out last weekend, but the alignment guy got more than 8* caster out of it so maybe that helped (-1.5*F,-1*R camber). The car did turn-in like mad.

I'm still learning what I like so am trying different combinations, hence my question.

 

So, what would you suggest for alignment specs for a C6 that is autocrossed but street driven too. Something not totally autox but a set of alignment #'s to give you something in the middle.

Bob B

p.s. Need to find a good alignment guy here in MA too!!

 

hope this is still on topic....
will the factory specs work if the car has been lowered??

 

This is from another post.... looks like good numbers... good for z51 or regular setup. Make sure caster is dead on.
----------------------
This is what I set it to:

L-front camber .... -0.8
R-front camber ... -0.8

L-front caster ... 7.9
R-front caster ... 7.9

L-front toe ... .10
R-front toe ... .10
Total front toe ... .20

L-rear camber ... -0.6
R-rear camber ... -0.6
Total rear toe ... 00.00
-----------------------

 

I would like to add:

By the time a car is converted into a real race car, the rubber bushings have been replaced by spherical rod ends and the compliance that causes toe out under braking has been eliminated. And that is why you can set a race car to zero toe and get away with it.

Toe out increases the responce to steering input, and if often used in race cars to alieviate corner turning push. Conversely, toe in deadens the responce to steering input and allows the car to track straight down the road. Moderate amounts of toe in does not cause tire wear.

 

Yes but there are many cars out there that see significant track duty and are still street driven...mine included.

I'm learning, but all I can say is

-1.5 Camber
8+ degrees caster
toe out

-1 Camber
toe in

my car handled better than I ever imagined and I'm in no hurry to change anything. I can't remember the exact toe specs but they were not severe.

 

It's funny, I had my '99 checked every year, and sold it this past October. The alignment never needed adjustment.
Were you having problems, or was your alignment specialist just keeping himself busier?

 

my M3 was brought in at 1000 miles for a bunch of things like brakes and such as per BMW. They also rechecked the alignment. Thats the difference between bmw and chevy but for the price, you can't beat our vettes

 

Sorry I've been off-line since my cornea transplant. Nate Dogs suggestions...

...are very streetable conservative track settings that should work well in all kinds of driving and give reasonable tread wear on the street. For auto-x you will probably want more neg camber both front & rear, but this is a great place to start.

And yes these are reasonable values for a lowered C5 and C6 as well.

 

Does anyone know if these camber settings are doable without changing any bolts? How much toe out front and toe in rear for an aggressive autocross set up (using the stock tire sizes)?

 

These camber settings are easily do-able with stock adjusting accentrics.

 

FYI

I just had my C6 aligned. The factory caster settings were 4.27-L & 5.14-R degrees. The tech adjusted the caster to 7.38-L & 7.55-R degrees, but he couldn't get the camber to go more (negative) than -26 degrees without adjusting caster away from the "preferred spec". The camber settings were -.43-L & -.50-R degrees.