awright2009

Heard you had to align it after touching the lowering bolts, but didn't believe it was really all that necessary, guess I was wrong

E.T.D. Corvettes

Thanks!

And not necessarily a stock alignment either (at least not on the camber settings). I'll post the numbers we used as soon as it's finished and also the results once I have some miles on new tires.

savage

let me tell you about my real world research( looking for autocross magic) last year i had a c7 base car that i traded with 6,000 miles on it( four alignments ) this year z51 car with 2,500 miles on it and just did my 3rd alignment( i think i found the MAGIC) anyway, i have found that neg camber does not by itself burn up inside edge of tires quick, its neg camber with tow in or tow out that does it. my alignment is not for any one who does not like to buy tires but it is for someone who wants to turn at a autocross.

TEXHAWK0

Even without being lowered, the factory camber settings and toe can cause significant inside tire wear...
I had my dealer do an alignment to reduce tire wear before I picked up the car... For regular highway driving, it needs to be close to zero toe in.

E.T.D. Corvettes

I just paid Tire Pros a grand total of $74.41 for an alignment. They have a new machine too...and they paid $70,000 for it. WOW!

So, they made adjustments to both toe and camber to help with the uneven tire wear. Keep in mind, this is really a touring setup now.

Here are the numbers that I came into the shop with today...

Left front camber -0.8 -0.8 Right front camber
Left front caster 8.6 8.4 Right front caster
Left front toe -0.10 -0.04 Right front toe
Left front SAI 9.5 9.5 Right front SAID
Left front included angle 8.8 8.7 Right front included angle

Front cross camber 0.0
Front cross caster 0.2
Front cross SAI 0.0
Front total toe -0.13

Here are the numbers that we went with today for touring...

Left front camber -0.6 -0.6 Right front camber
Left front caster 7.3 7.3 Right front caster
Left front toe 0.00 0.01 Right front toe
Left front SAI 9.1 9.6 Right front SAID
Left front included angle 8.3 8.6 Right front included angle

Front cross camber 0.0
Front cross caster 0.0
Front cross SAI -0.5
Front total toe 0.01

I'll post a handling review in the next couple of days and tire wear findings once I have new tires on and some miles on the car.

John Ulrich

After a couple of highway trips I still had a slight "drift" to the right after the dealer did an alignment under warranty. I visited my dealer with GM document ID: 3971340 that has the revised 2015 alignment numbers for Corvette. (I cannot find the post that had it in a printed format). Their alignment rack computer did not have these numbers yet.
Bingo, that seemed to do the trick. Nice neutral wheel again.
FYI, mine is a '14 so don't let the '15 throw you. The service adviser pulled up the document on his computer in seconds so you don't need to find the printed one.

Update: After a weekend of 2 lane and 4 lane highway this has it nailed! I'm on the road and my numbers are back at home but the suggested GM numbers for camber are left camber is -0.2, right is -0.5. Those two numbers are drill in my head because they were the only numbers off from the printout for the first alignment.

hawkgfr

They (the chevy dealer) made your alignment worse....They wouldn't wear that bad had you left it alone after you lowered it IMO...


Go to an alignment shop you trust not the chev dealer imo again...good luck.

May as well get new fronts at least...those are gone.



edit for sorry I missed your update post lol... my bad...

BlueDevilZ51

I found these alignment specs when I did a search. I'm looking to bring the car in Friday for an alignment and was hoping someone will confirm these alignment specs for a 2015. Thanks

John Ulrich

See post #26. Give the dealer that ID number. Camber for the left front is now -0.2, front cross camber 0.3

Horsefly

I hate to say this, but some things are better left alone. At least until there is sufficient
data to support the changes that we all want to make to the factory settings. Ideally, the tires should be carrying the weight of the car in the optimum position. Coming new from the factory, we should expect that is where the car is set up when delivered. Lowering or raising the car moves the weight around on them where they contact the road.
Lowering to reduce a cars stance a half an inch or so just ain't worth the risk to the alignment...or the attitude of the suspension/handling. Early on, I remember seeing a lot of posts regarding "Lowering on Stock Bolts" and always thought to myself........dude, you're changing the geometry, ...you better check your tire pressure & tire wear often. Or, find an expert alignment guy that can make proper adjustment.

What do you think GM would do with the same wear pattern had you not adjusted the lowering bolts? I want to lower mine one day, I just got to find an alignment shop that I can trust....

Just my 22 cents.

John Ulrich

I'm thinking that an alignment should "square" things up when put back to the factory numbers. If the contact patch is the same if higher or lower in stance then the tires should wear the same.....at least that's what I'm thinking?

owc6

I would get an alignment asap after lowering.

But then, again, I have been ridiculed for advising getting an alignment at every oil change on the Vettes. No one has ever shown me why this isn't good, and I've gotten extraordinarily good miles out of all my tires, which has more than paid for the alignment cost over many hundreds of thousand miles.

owc6

Then, there's the sticky-wicket question of whether the OM meant to put the "rotate tires every 7500 miles" in the OM. Because:

Those tires aren't symmetrical should not be rotated based on that fact alone.

That would require, un-mounting and then remounting them every time.

droideka

jeremy,

i lowered my car with less than 100 miles on the clock back in the day as per your original instructions (Z51 w/MSRC). i never intended to get the alignment checked afterwards and decided to roll the dice and see what happened.

i just went to the garage to check my tires at ~4100 miles and frankly couldn't believe how perfect and uniform the surface is across the entire tread. no signs of cupping, shoulder wear, irregularity or anything else abnormal. i don't do any extended cruising on the highway, mainly just short trips around town with lots of WOT, heavy braking and aggressive cornering. your wear (as previously mentioned by another poster) looks like a combo of driving a lot of straight miles on aggressive camber and toe-out settings. sorry this happened to you, brother.

what did your rear toe look like pre-re-alignment?

Mr Guns

I checked my tire wear after seeing this thread, and my fronts are wearing quite a bit more on the inside. My previous C6 also wore the fronts more on the inside. It was aligned to factory specs. I might have my C7 aligned to 0 camber for better tire wear.

dbdave

They can be 'rotated' side to side.