Guessing I need an alignment...?

[Porsche Chick]

Overdrive, What, exactly, are we supposed to be looking at in the pictures?

[mountainman]

According to everything I have read when autocrossing or other hard cornering you do need to up the tire pressure somewhat. How much seems to be less clear. According to my wheel guy extra pressure also helps to minimumize wheel damage when we hit the inevitable potholes, etc. As the economy worsens and governments cut back on road maintenance we are getting more road hazards out there. Since I do most of my driving on curvy mountain roads I add about 4 psi to the recommended pressure on both boxsters and my C4 and have found better response and more even tire wear with less wheel damage. Just my experience. Try a few things and do what works for you.

[thstone]

Originally Posted by Porsche Chick

Overdrive, What, exactly, are we supposed to be looking at in the pictures?

It appears that the photos show what is called scalloping or cupping of the outside edges of the tires.

Unfortunately, this problem can have several causes but the cheapest and easiest fix is to start with an alignment and then go from there, but you should be sure to have the shop do a full inspection of your shocks and suspension just to be sure.

Once the tires are cupped or scalloped, its nearly impossible to "undo" this wear pattern. Some people will have the tires swapped so the cupped outside edge is now on the inside.

For reference, here is an example photo of what extreme cupping or scalloping looks like. Of course, I chose the most extreme example that I could find to make it easy to see in a photo. In more typical situations, cupping is usually more subtle, so it is best found by running your hand over the tire and feeling the up and down wear pattern than seeing them.

[woodsman]

Overdrive: new tires, massively stressed look just like that or, tires grossly underinflated and overstressed--slow leak? Either way they don't seem to be rolling over too much and the trailing lip on the edge of the tread blocks is indicative of tread deformation caused by severe loading (hard cornering)...autocross