RS4 chunking....what are we doing wrong??

kevlarcorolla said:

 I've never seen toe in wear the inner edges of a tire.

Now you have.

Because the inner edges are all that is on the ground with that wheel/tire/camber setup

In reply to red_stapler :

I meant just toe in,I get that I have more then one contributing factor in this case.

Toe-In would wear the outside edge of the tires.

In reply to LanEvo :

Agreed there.....Calabogie is a fantastically designed track but its paved with 40 grit sand paper.

 At least its smooth,Shannonville is rough as hell AND coarse

In reply to Tom1200 :

Exactly.

Tom1200 said:

Toe-In would wear the outside edge of the tires.

Yeah, I've worded this poorly.  The problem is not toe in, it's not enough toe out.  My understanding of this wear pattern is based on how it was explained to me like 4 years ago on another forum.  I dug up the post to quote it here. 

Markdaddio said:

As you add negative camber, you actually need to add some toe out to negate the camber thrust forces that are working against each other. I run -3 degrees on the front of my vette and couple that with 1/16-1/8 inch of toe out to get the best wear results. I drove my car to 1300 miles each way to Nationals with no major inside wear. It will show after 8000 to 10000 street miles though. Each front tire when cambered produces a vector force towards the other side of the car. if both sides are cambered, these forces fight each other going straight down the road. This is the reason why negative camber at the front makes the car change directions so quickly. The pushing together forces that cancel each other manifest in tire scrub if the tires are pointing straight ahead. For every car and camber combination, there is an amount of toe out that will minimize the scrub of the tire.  You can use coast down testing, or do like I did and just run 3/32 toe out for 3 degrees negative.

In reply to red_stapler :

We had the car aligned to 6mm total toe out,ripped the inside on saturdays 7hr.

 Pulled it back to 1/16" total toe out sat night and made pretty much zero difference on sunday.

 Not convinced toe had much to do with it at this point.