Just had my 2 rear tires replaced because they were wearing inside to fast but my car still handled great at that time. I replaced them with the same Nitto Invo tires and also did an alignment to correct the uneven tire wear. Soon as I got on the freeway I noticed my steering was very darty feeling and when I got on my favorite on-ramp my car felt like it was floating, around 80+ it was usual felt unsafe since usually feels so planted. When I got home checked tire pressure adjusted them not much difference after another test drive. I took back to the shop next morning and they redid my alignment to GT2 spec as close as possible since its stock suspension. On the way to work after the 2nd alignment I didn't have time to test drive before taking the car back I noticed it a bit better but still darty and same on-ramp I didn't feel as comfortable as normal. So my question is are these alignment numbers within normal street conditions for daily driving I just want it to drive like it did before the new tires? My shop wants me to bring back in morning and put old tires on to see if it behaves any different

Thanks any advice appreciated.

 

its normal for new tires to feel like there actually moving around...give it a few days for
that shinny crap to wear off the tread..if you still have a problem, take it back ask the guy to drive it while your in the car.

 

I did have him drive with me on the first alignment and he noticed the darty feeling as well before he did the 2nd alignment. I have put over 200 freeway miles since yesterday when I picked it up from 2nd alignment. I figure shinny crap should be gone by now?

 

Wearing the rear inside edges too fast is a sign of too much toe in, too much negative camber or both. When you asked the alignment shop to remedy the inner tire wear problem they more than likely decreased the toe in and maybe some of the negative camber. With near neutral toe the back end will tend to wander and weave when driven in a straight line. With less negative camber the back will not feel as planted in turns. With GT2 spec alignment these issues will be corrected but you will once again experience premature tire wear on the inside edges. The cost of great handling is short tire life.

Looking at your alignment specs before indicates toe out on the right front and toe out in the left rear. I'm surprised the car even tracked in a straight line on the freeway. This was just a bad alignment job to start with. Hope they didn't charge for the corrected alignment as the first one was way out of spec.

 

How much tire air pressure are you running?

I've noticed that with my 19" wheel and tires, if I run what it says to run on the gas door lid, the car does not feel too stable, much like what you are describing.

I lowered the tire pressure a few PSI and the car felt much more planted again.

 

What kind of shop did you use?!?!? Those are horrid numbers!

Your front has neg camber (good) on the left, and pos on the right...

ALL tires have too much toe. Shoot for 0.02-0.03 front and rear.

Combined with toe, the different camber can cause the front tires use different 'sides' of the trad to grip the road based in how much they are loading...

Rear camber is out- 1.1 on the right is OK, but 1.7 is over the limit... not the end of the world, I run more, but a spec is a spec- it should match the other side and be under 1.5. ("Match" more or less, )

Toe is what kills tires...0.01, 0.02, 0.03 will give you the lowest wear, and satisfactory handling.

Many people/sjops just get the numbers "in the green" and call it "aligned"...that's not acceptable, IMO- finding someone that is willing to discuss it with you and take the extra effort is worth the time. (And a good $tip.)

A

 

May be you can ask the shop to change the front toe to almost zero and see!

 

Thanks guys I appreciate the feedback. I have played with the tire pressure I run 19's running 37psi front and 41psi in rear. I have put about 400-500 miles on the new rear tires still not much difference but a tad more planted. My shop is paying for me to take it to Porsche dealership tomorrow morning for its 3rd alignment hopefully this will solve the issue. My shop has been very helpful and trying to make it right.

 

Those alignment specs are totally off the wall. Go to a shop that knows what they are doing.

 

So the dealership called me today they found out my eccentric bolts in the rear were bent, he said he could move the bolts with his hands that's how lose they were. The dealership didn't have the part in stock so I get my car back tomorrow after they replace the eccentric bolts and re-alignment and I should be good to go! I'm just glad they found the problem just hope it solves everything.

 

Glad to see that they found the culprit. Makes you very frustrated when you feel it and scratch your head.

 

And what toe will the Porsche dealer set front and rear to??????

There is a big range, not "one number"...so unless YOU tell them you may not get the best alignment... like I said, keep the toe near the minimum side of the range and you will get much better tire waer

 

Update got my car back this afternoon from the dealership they replaced both left&right eccentrics screws and re-aligned my car for the 3rd time.
My car handles a lot better but only got to put 7 miles on it today so this weekend I will be able to get more aggressive and see if everything is like it use to be. It at least feels safe and solid now even though I didn't really get to drive it hard today. Only complaint I had today was when I picked my car up from the dealership I could smell that clutch. I got the service adviser to come check it out and he smelled the clutch too. I think who ever test drove it either didn't know how to drive or was having to much fun

I attached new alignment numbers what do you guys think of these settings?