So, I've tried to read through the numerous threads on this subject for several hours now and they've been informative, especially if I wanted to track the car. Which, increasingly, I do not. That is mainly because I can only afford to choose one significant hobby and aviation is it for me.

BUT, it doesn't mean I don't like to enjoy driving my custom factory ordered 2019 Z07 Sebring Orange monster every chance I get. What is disappointing for me is the ridiculous tire wear I'm seeing. Corded and steel plys exposed on all 4 wheels at less than 13K miles, inboard side - due to excessive negative camber and probably in concert with other settings that exacerbate this condition during "spirited" driving.

This all started when I found my destroyed tires and bought new ones (stock Michelin PSS 285 front, 335 rear run flats on stock 19x10" and 20x12" wheels) - Note, I will get on my knees now and inspect my tires regularly going forward.

After much research, primarily on this site I concluded that I needed a mostly "flat and straight" (minimal negative Camber - 0.5 to -0.7 degrees front, -0.3 to -0.5 rear, Toe set to -0.03 deg. or so front and rear all around, and +7.5 degrees front caster and + 0.8 deg. rear caster), for my Strictly Street Driven car in Brevard Co. FL. (flat country)

These numbers, unfortunately, could not be achieved according to my local Bob Steele Chevrolet dealership technician in Merritt Island FL.

Nice guy, but he said that when he attempted to adjust rear camber to such "flat numbers" the rear toe goes positive (toe in). I asked what the rear Caster measurement was and he said, "they can't measure or adjust caster" here. He thought it would take a special tool. So he set the negative camber on the rear to the flattest setting he could and that was -0.9 degrees, both sides, and rear toe to -0.03 degrees both sides.

I didn't know there were these limitations to adjustment for the rear...comments appreciated.

For the front, I requested Camber -0.6 deg., Caster +7.5 deg., and Toe set to -0.03 degrees (toe out). He nearly achieved that with -0.7 deg both sides and met my caster and toe request.

I'm hoping to not destroy another set of tires in 13K miles so would appreciate all polite comments and recommendations on how to best maximize the life of my new tires. Don't say keep your foot out of it. The tires had NO wear on the outside of the tires I threw away. The "Before" camber on rear was -1.4 deg. left and -1.3 right, and front camber was -1.3 deg. left and -0.8 deg. right.

I'm wondering about my rear caster setting, and the overall rake of the car front to back with what I've read here. Might it be that my rear ride height is set to low? I've read 44 mm higher in rear and I don't think it's got that much rake.

And, why can't the rear camber be set to shallower/flatter numbers? Special tools? Special equipment? Remove washers on Upper control arms???

Thanks for your input.
-SubsonicVette

 

My understanding is it takes a special tool to set the rear camber and the tool cost is about two grand, few Chevy dealers even have it.

 

Caster is what takes the special tool. Camber and toe should have a fairly large range or adjustability.

Caster measurement is taken off the rear spindle and a digital angle gauge

 

I had no trouble adjusting camber and toe in the rear. I don't know why he would have a problem unless he doesn't understand the C7 suspension. Adjustability is what makes this car handle so well.

 

I've always had the rear and front set to a small toe in or 0; rwd tends push on the fronts and cause toe in condition, so a 0 should be fine. The natural toe out on the rear tires say you should run a little toe in, which should keep the car straight under hard acceleration and braking. If you notice the car doing hard kick outs on hard launches or gets squirmy under hard braking in the back, your toe out condition is to blame.

In the back, toe in is also better as the rwd pushes outward as it it accelerates, again nothing too drastic, you just want the natural bushing give to keep it relatively 0 while under load.

Using this with minimal camber 0-0.5 usually gave my C6 cars really good even tire wear. On my C7 z06, I'm running -1.2 camber and the tire wear is still good a year later (I'm going to be swapping out my rears due to cup 2's hitting end of life before I have any inner cord wear.

I've never had anyone complain that the settings I've requested is too hard to do on the corvette platform. It's just a bit annoying as changes to one side tend to influence the other side, but a good shop doesn't say its impossible, just takes the right time needed to do it right. Any shop that says otherwise is probably not giving you the right alignment which is why your tires are cording.

 

I would have said zero toe or a shade of toe in both front and rear. Toe out in the front gets you better turn in but your other alignment settings indicate you aren't interested in hard corner carving. Toe out in the rear gets you a nervous car. You may get a lot of tramlining with that setup.

Bill

 

You need to take it to an independent alignment shop or maybe another dealer. I had the dealer tell me that they couldn't get mine to the DSC specs but what they really mean is they don't know how to manipulate one angle such that it puts the others in the desired range. They also charged me $350 for the pleasure which I declined to pay since they didn't get the job done properly. I took it to an indy shop that does alignment using the same Hunter machine for all the weekend racers around here. It took him 30 minutes, cost $150, and he has a rear caster tool he machined himself to measure that angle. Set it exactly on the money where I wanted it. Don't believe the dealer, that line is a cop-out. Ask your local Corvette club guys who track the car where they take it or find a local SCCA chapter and ask around. There will definitely be a shop around you that can do it.

 

Have you ever requested -0.4 degrees camber rear? Try that and let me know how it goes.

 

I took my C7 Z06 / Z07 to an independent alignment shop.

They were able to reduce the negative camber for both rear wheels to -1.4. and to toe to 0.01. The front tires are at -0.9 camber and toe set to 0.05.

They did indicate they couldn't reduce all of the negative camber of the Z07 suspension design.

 

I think the washers were designed to affect the camber by 0.4 degrees at a time, so -0.4 with a +-0.2 is entirely possible. Note that depending on your cars condition and age, that variance will make it tricky to get it bang on. I don't think the z06 can be zeroed out either, much less a z07 or zr1. My alignment tech got 0 on the rear and front for my c6 when I wanted to do my road trip to bowling green and myrtle beach. I ended up liking the street setup so much that I left it that way until I went to a c7 z06. I currently am running -1.2 camber front and back as I am not near the limits of the car but want semi decent tire life for my cup 2s.

I think you coule possibly get a 0 camber with an offset adjustment on aftermarket rims. By pushing the tire out farther, ie towards fender edge adds a small amount of positive camber.

 

I was having the same issues, you will be good with -1.0 camber on all 4 corners, I did -1.4 in rear, if you go any farther the rear tie rods run out of adjustment, unless you mess with the washers on the upper control arms, good luck find a tech that knows this, all you need is a digital angle finder on the rear spindle to put the spindle at 90* to the ground, the gm angle finder setup is nice cause you can watch the measurement while adjusting the camber and caster adjustment. I have 2 washers on front upper control arms and 1 washer in the rear upper control arms. could of used 2 washers in rear upper also cause my rear tie rod was maxed out on L/H. but was right on for toe. yes 0.03 is the spec for toe out settings. hope this helps.

 

As Bill said, if you're not tracking and looking for tire life mainly, closer to 0* toe is best. The adjustments are not so easy on these cars as the camber & caster are adjusted from the same 2 points. Annoying for the techs. You change 1 to a spec and the other setting goes out. You get that one and the 1st one is now out. back & fourth until you get it.
I don't think the caster is too important for your use.
I am friendly with my guy so I am under the car with him when he does my alignments to the specs I bring. I make sure they're VERY close before I tell him that it's ok. And if I drive away and don't like the feel or if the steering wheel is off center I drive it right back and back on the rack I go! lol

Ron

 

Not to hi-jack the tread,but does anyone know if GM made changes to Corvette plant when they did the paint shop and other things in 2018. Do the 2019 C7 ZO6 cars have better specs off the assembly line?

 

This should help, the 2019 Z shares many of the ZR1 upgrades. For the average Joe those might be irrelevant.
https://www.corvetteforum.com/forums...-2019-zo6.html