FirebirdStud

iTrader: (5)

Hi all.

I have a daily driver bird, 95, full weight. I have Goodyear Eagle GSD2 rubber, 275/30zr18's up front and 295/35zr18's out back. They are on Vette chromed out Z06 wheels.

I put the rubber on about 7xxx miles ago, and did an alignment myself at the time. (I work at a Chevy dealership) I did the alignment to stock specs.

I have had the tires set at 32 to 34 psi since they were put on. (I say that because I looked at my log, and the first summer was 32, the second summer was 34... not sure why I changed, but I did.)

I checked tread depth, and the rears are at 9/32nds all the way acrossed the face. The fronts are at 9/32nds in the middle, and the outsides are at 5/32nds and the insides are at 6/32nds.

Anyways, looking at the car now, the outsides of the front tires are worn down more than the middle or the inside. The car tracks fine, but Im wondering if I need to adjust the alignment to specs other then stock. I have a built motor in it, with a Dana 60 and a viper conversion t-56... I drive it hard. I like to take corners fast as well... Is this why the front tires are wearing so quickly on the outsides??

What tire pressures work well to help combat this, and should I re-align it to some other spec??

I am trying to get a feel for what other people have experienced and have learned what works well for these cars.

I do want to stress, this is a daily driver. I will be taking it on a 9 hr road trip this thursday for a family wedding, so I dont want really agressive alignments where the inside of the tires will wear from agressive camber... trying to find a happy medium I guess..

Many thanks!!!
Cody

FirebirdStud

iTrader: (5)

Here is the outside measurement


Here is the middle measurement


Here is the inside measurement

z28bryan

iTrader: (7)

The outside tire wear is pretty common. I think stock alignment range goes into the positive camber range. It's real bad for tire wear. Try to get alignment set to about -.5 camber with even toe. It will be better for tire wear and for performance

Xsta Z 28

iTrader: (2)

With inside and outside wear being about equal, IMHO I'd say alignment seems fine . . . fronts sound to need a touch more air pressure. . .

FirebirdStud

iTrader: (5)

I also swung by a goodyear dealer here and they said to use a tire crayon and draw a line across the entire face, drive it for a bit, and look to see how it is wearing to see if the pressure should be adjusted...

They told me to start with the factory recommended tire pressure, which is 35. Ugh looks like I have been running a little under-inflated. Damnit. I am gonna throw it back on on the alignment rack at work too just to check it out tomorrow. Wondering if there are specifics to use during the alignment instead of stock specs... like the -.5 degrees of camber mentioned above..

JD_AMG

Stock alignment is known to wear the outside of the tires like that. And FYI the factory recommendation for tire pressure (at least on my car) is 30psi front and rear, check the inside of the door for the sticker.

05c15builder2009

rotate ur tires every 3 to 5k miles. they will wear more evenley and last longer.. hard corners dont help much as well.. goodluck

99FormulaM6r

iTrader: (2)

I don't know if he wants to rotate the 295's up front and the 275's out back

I'd say tire pressure should be checked, might be a bit low, also check your alignment.

FirebirdStud

iTrader: (5)

I think Ill give this a shot. Anyone say no to this?

FirebirdStud

iTrader: (5)

for some reason my door sticker doesn't say stock tire pressure.

But I thought the LT1's were 35psi...

FirebirdStud

iTrader: (5)

I just got back from the road trip to the Black Hills. I was too busy before I left, but here are the readings from the alignment:
BEFORE:
Caster
left 4.9
right 5.0
Camber
left .3
right .2
Toe
left .25
right .2
total .45

AFTER
Caster
left 4.3
right 4.4
Camber
left -.2
right -.2
Toe
right 0
left 0
total 0

Im a little perplexed by how far off the alignment was. I guess two years of daily driving will throw things out of whack?
I checked the ball joints and tie rod ends and everything was snug before I did the alignment.

Driving out to the Black Hills and back (1500+ miles total) was like a dream. The car tracked straight, rolled into corners nicely and held the path firmly. Im very glad I checked the alignment and corrected it. I also pumped up the tires to 35psi.

I haven't had a chance to re-evaluate the tires yet, hopefully tomorrow.

So that is the update so far!