Well I had the car aligned two weeks ago and it was great. Did an HPDE, didn't hit anything, and driving home I have a leftward pull. I know prior vettes used eccentric bolts and they could slip. Same deal on the C8? I suppose a myriad of other factors like tire pressure, track rubber on the inside of the wheels, uneven tire wear from the HPDE could all be culprits too. Not super happy if I have to go get this thing aligned again in such short timing.

 

Yes, it uses eccentrics. When we did the alignment on my C8Z it was surprising how tight we needed to get those eccentric bolts. You are not supposed to use power tools, but using a socket and box end wrench, it took a lot of torque.

 

I don’t have my Z06 yet, but with my GT4, I noticed after track days, driving on the way home, it pulled one way or another, depending on which way track ran. So, as you continue to drive it, it should start to get back to neutral again, so drive it good amount and see. I do know that I also noticed lots of track rubber on the tires, so this should go away as you drive more, so all should be good. Alignments hold pretty damn well!!

 

I always put a dab of paint on the eccentrics after I do an alignment just to be sure. Even after hitting curbs repeatedly, I've never had one move yet.

 

MFT is the correct amount of torque for the eccentrics. Ignore any and all torque settings described in the service manual. Twist it as if your life depended on it.

 

If the OP didn’t hit anything, it’s just simple tire wear, track rubber stuck on wheels, etc, the odds these bolts came loose are extremely low.

I know on my GT4, took me a few times on regular road drives until car went back to neutral alignment. You’ll see.

 

question for brand new Z06, is it true that most of the time the alignment is way off from factory? and one should get an alignment done asap?

 

I took mine for an alignment at about 1000 miles on it. Felt like it was never quite right when I got it and measuring camber in my garage came up with different values all around. At least on my car, the alignment was way off. Toe was out on both left front and left rear. Camber was different on all four corners.

I'd definitely recommend an alignment. At least ask them to measure it as it current sits.

 

If you want the dealership to pay for the alignment, complain that the car pulls to the left or the right rather than say "I need the alignment checked". If you tell them to check the alignment they will bill you.

 

Every Porsche I have ever bought had different and incorrect alignments, so I can surely bet the same with any C8.

 

The issue I had with this is they tend to tell you things are fine. Or they checked and it's in spec (didn't check). Or they centered the electronic steering sensor and didn't need to align it. You see what I'm getting at. Getting a dealer to pay for or somehow warranty repair an alignment is nearly impossible. They always look for a way out or try to blame the owner/driver for hitting something.

 

I always lean left.

 

Dealers aren’t going to give away free services. When I bought my GT3, I said it pulls a bit, they did take it to alignment machine, they said it was within parameters and if I wanted any specific alignment, it was $X amount to do so.

doozy

 

I was an alignment tech for 5 years...I agree with the above. Are the front tires directional? If not, I'd recommend swapping the two front tires side to side and see if the pull changes to the other direction. A slipped steel belt was the most likely cause of extreme pull when I did alignments...much more likely than the alignment causing it.

Also, even if the eccentric bolts did move, those bolts "typically" (not sure on the C8) are used to set camber and not caster. It is very unlikely that camber being off would cause a pull...it would have to be so far off that you could see it from the front of the car in an obvious fashion. Caster is typically what causes pull.

 

https://amtmotorsport.com/collection...-camber-kit-c8

 

1. Can it slip? Yes... but it's very rare and would only do so if the tech didn't tighten things properly. I've never had one slip from the factory.

2. OEM LCA spec is 111 ft/lbs + 90-105 degrees. We just settled on 125 ft lbs and called it good enough

3. Toe will make a car feel much more darty and make it hard to center the wheel and it will pull more based on the angle and crown of the road.

4. RE: the AMT link above... I used camber blocks on my C5s all the time, but on the C8 the caster is sensitive and LCA blocks require you to shim the UCA which means converting to studs so you don't wear out the holes.

5. The alignment tech guy above is a bit off... the LCAs set camber AND caster on these cars and rear caster is critical to bump steer plot and the car feeling right

CLIFFS - These cars are a bitch to align right and a good race shop will take 3-4 hours and I'd never use the dealer unless they were a known "track prep shop" dealer as some do exist.

 

What alignment do you recommend for dual duty C8Z? I don't have a good race shop in my town, the dealer vette tech aligned mine. -2.7 front camber with 0.1 total toe in and -2 rear camber with 0.1 total toe in. First track day out - I took a little more curb on 1A at NCM, then the alignment slipped. Steering wheel preferentially is turned right and car pulls left. I'm taking it back to them next week and ask for higher torque on the eccentric bolts. I hope to avoid this happening again.

 

For experienced drivers, -3.0*F and -2.5*R. seems to be the most popular setup. I have my non-Z07 at -3.0*F and R and light toe-out at the front and light toe-in at the rear.

 

The torque specs on the eccentric bolts used in alignment are confusing for the C8 compared to the C7. With the C7, you set the wrench to a specific torque and you tightened it until it clicked. For the C8, you torque it to 111 lb/ft on the first pass, then you torque it an additional 90-105 degrees on the final pass. This is a pain in the butt way to torque a bolt that is NOT a single use fastener, and it's a LOT of torque compared to the C7's eccentric bolts.

I do not think most shops are doing this correctly when they do an alignment. I really doubt they are measuring the angle for the second pass the way they are supposed to. I think the are using the same torque (roughly) that they use for all other GM eccentrics, and I think they are coming loose left and right (By that, I mean that there have been 4-5 people who told me their eccentrics shifted on track). Not loose as in falling off, but loose enough to slip the alignment. There are a ton of people reporting slipped eccentrics on the C8, I think this is the reason why. There is even an aftermarket company out there offering a set of eccentrics for the C8 that are designed not to slip.

I'm not saying a slipped eccentric is your problem. I'm saying that its possible, and appears to be much more possible with this car than previous Corvettes, even if it's not the car's fault.

 

Agreed; 111 lb ft + 90-105 degrees is WAY MORE than 111 lb ft, or 125 lb ft that the shop used for one of the forum members. It might vary, but someone should do that with an electronic torque wrench to see what it peaked at. I personally bet it would be in the range of 200 lb ft, or even more.