Boomer111

I had the 08 aligned as follows:

Front camber 0.0 both sides
Front caster 7.8 and 8.0
Front toe .07 and .06

Rear camber 0.0
Rear toe -0.02 and .00

The tech told me the rear left side toe actual was 0.0 . He adjusted for driver weight.

I am looking for best tire wear. Car seems to drive ok, but I do feel a little bit of wondering or sensitivity to steering change. ( some of this could be from coming back to stock 245 from 275 in steer tires).
Cornering has the car at max G force wanting to lift and slide a bit, not what I am used to.

I wonder if it is just switching back to the stock Z51 tires&rims from the Invos 275/305 on wider rims?

Looking for members experiences with my new alignment specs.

I was thinking of going back and adding 0.5 camber in front with zero toe and leaving the rears at 0.0 camber and the zero toe.

I think I may be over thinking this!

Street only with no real hard driving except maybe very infrequent twisties fun and then not at edge.

RicK T

Camber at 0.0 will give maximum tire longevity but is not good for handling. There are some here who have gone that far but most don't. A common suggestion is camber at -0.15 to -0.25 for a nice combo for tire wear and handling. YMMV

You know or have seen the factory spec sheet, yes?

Kaldar

its wandering is because you have 0 camber, the whole tire is contacting the ground which gives it a greater tendency to wander or 'tramline'.

if youre coming from 275 tires upfront it could feel a bit more sensitive with the 245s being they are easier to maneuver aka lighter.

IMO thats a pretty lame alignment, especially for a corvette.

You've got the right idea by adding some negative camber, i would recommend this following setup for a good compromise between handling and tire wear;

Front:

-.5 camber
0.5 to .8 positive toe (toe-in)

Rear:

-.3 Camber
0.5 to 0.8 postive toe (toe in)

the toe in on the front will give the car a more stable feeling at higher speeds and having the rear tires toed in a little will help give the rear end more stability when getting on the gas while driving through the twisties. A more aggressive setup would be just a tad bit more camber such as -.9 front and -.5 rear but thats still conservative IMO...

I run -2.0F camber, 1/8th toe out, 7.5* caster, -1.5R camber, 1/8th toe in rear. I track my car and i drive it on the street

Boomer111

Thanks I have seen the specs. and understand I was going outside them.

Boomer111

Not really sure if it is wondering...but think it is just a bit to light feeling.

Thanks for the reply.

eboggs_jkvl

I'm the bad guy that is pushing 0 camber. I ALSO very clearly state that it is for highway and calm city driving. If you're testing the max G force, you are NOT heeding the part where I said add -2.0 camber or more if you want to test the G Forces. Negative camber is going to wear the inner edge of the tire, plain and simple. If you want the tires to last for longer tire mileage then 0 camber is your friend. You want to test the twisty feel? Fugedaboudit!

I am running 0 camber and 0 toe. I don't wander or tram-line.

Elmer

AORoads

this is pfadt engineering's specs:

corvette-alignment.pdf

and this was modshack's posting for his '08 (believe it comes from here: http://forums.corvetteforum.com/c6-t...-wheels.html):

don't know if it will help, but I'll send you the actual alignment chart via email.


12-07-2007, 01:46 PM #2
Modshack
CF Senior Member

Member Since: Feb 2007
Location: Greenville NC

You're correct to be concerned about factory alignments. i figure they have 3 minutes to dial in 10 adjustments. Not to confidence inspiring, and proven when I took mine to an independent for an alignment.

The spec ranges are so broad that it can vary from precise to sloppy but still technically be in spec. I wanted mine as close to centered as possible but I drive the car fairly hard so figure my wear will be pretty even. If you're just a cruiser and don't put any premium on handling, then reduce the camber front and rear. Some Zero this out. It will reduce potential cornering ability though.

Top chart is my '08 at 6000 miles with nothing hit...Pretty much as it came from the factory. Note the items in red which are outside even the broad factory specs.

Bottom chart is after. the car feels much better BTW..

Last edited by Modshack : 12-07-2007 at 01:56 PM

Boomer111

I have read your posts. I knew going in that I was setting the car up for max tire wear. I am still not sure if I like or dislike the hiway steering feel. I am thinking I am experience of changing wheel/tire width has a lot to do with what I may be experiencing. The speed I felt the car slip was pretty hard cornering. probably not going to do this much. High speed stability would be more of a concern. I have wasted tires on numerous cars before and just do not want to go this route again with this car. To expensive.

Looks like I'll be going back and getting a redo to the favorable side of the OEM specifications for tire wear.

Thanks to all for some clarification.

fnsblum

I installed new Kumhos when I bought my 08 last June and had the front camber set at -.4 I just measured the fronts again with 8500 miles on them. Both have exactly 8/32" on the inner and outer edges. The car feels very neutral. Later! Frank

Boomer111

Thank you for posting, this is the range I am heading for, factory nominal specs.

Mez

If you set at 0° toe-in, when the car is at speed, rolling resistance will compress the suspension bushing rearward slightly and will cause it to actually toe out a little. You want some toe-in to eliminate the 'light' feeling you are sensing.

There is a good reason all OEM manufacturers recommended setting have some camber and toe-in. I suggest you Google alignment theory to find more information on getting the set up you desire.

99c54me

I had camber set at -0.5 when the car was new.

20,000 miles later on the runcraps and wear across the tire appears perfectly even.

From the posts I've read over the years it appears a wide range of camber works for even wear. Feel would be the thing that is not quantified, unless someone has tried various settings.

Boomer111

Thanks I understand now the role of rubber bushings vs the race hard ones on toe.

Re learning a lot that I thought I already knew.

torquetube

For street handling, dead-even wear and good tread life, do this: http://forums.corvetteforum.com/1565502174-post14.html

I Get over 30K miles from PS/2 ZPs (on my second set now), and around 20K from F1 Supercars.

SG4206

I agree with your numbers to increase tire life.

IMHO leave all your new settings alone , except change the rear toe to .3-5 per/ side. I believe your feeling a wandering front, is actually rear steer. I had this myself trying to maximize tire life on other vettes.

If you have an understanding alignment shop ;changing one thing at a time ,will isolate the dynamics of the suspension and you will learn from cause and effect .

Boomer111

I went with the Pfadt street settings.

I do not put many miles in the car so might be awhile to see the outcome regarding tire wear.

After experiencing the zero camber I will have to live with new settings.

Thanks for all who helped, including a couple of call to Pfadt.

MY numbers are:

Front
Camber -.8 L&R
Caster 7.9&8.0 L&R
Toe -0.05 L&R

Rear
Camber -.5 L&R
Toe -0.02 L&R

The guy worked on it for 1&1/2 hours to get these numbers. The machine Hunter 600 is very sensitivity.

The Rear toe specs where actually zero when done individual but when combined for print out they showed -0.02 the fronts went up too. He said that the toe is zero but to show on machine print out it would have to be in positive territory. Whatever... pretty minimal at worst.

These are in degrees. So 2 hundredth of a degree, amounts to nothing really. Then you have to aske yourself the calibration properties of said equipment etc etc.

Boomer111

The Pfadt Street recommendation was right on. I'll have to wait and see how the tire wear is but handling is suburb.

I think to truly understand a situation one has to experience each end of the spectrum, so to speak.

While it cost me two alignments I feel solid in my decision with the Pfadt Street set up.

Thanks to those that pointed me in this direction.

I was able to give it a good test today with 40-50 mph turns, lots of them. The car felt better than it ever has before. Very solid with no surprises.

Unless the tire wear is just nuts I think the car should come this way from the factory, making it a handling dream.

The Pfadt Street looks like this;

-0.8 front camber with -0.5 rear camber and close to zero toe in all four corners as you can get.

Really sweet set up.

Big improvement over the stock nominal settings of -0.45 front and rear, which is what the dealership did.

I have no doubt that the experimented zero camber/toe I tried will give better tire wear, but the handling was sorely lacking. Even in straight freeway use, to say nothing of the carving.

Glad I am done with this, now what else can I screw up trying to make better.

eboggs_jkvl

I'm glad you are happy. One point. Watch the inside 3 inches of your tires.

Elmer

Boomer111

Will do, but it might take a while considering the time I spend driving the car.

I figure the date of mfg. might come into play quicker than tire wear.

Elmer, the zero camber just left the car feeling skittish and that was just with one on ramp turn. The test I did with the Pfadt settings would of left me in the trees at an even slower speed.

This was a good lesson learned for me...handling is super with the increased camber, and the car feels safer.

No worries I like trying different approaches to see which I can live with.

One reason why my golf game is always in flux, always trying different swings/shot making styles.

I get bored easy.