Your experiences with camber and tyre wear
 

Just wondering what your experiences have been with regards to camber and tyre wear.

I'm not talking about stupid amounts of 'stance' camber, but more like 3-5 degrees positive on the front and the assumption that an alignment has been done to correct the toe in (which obviously WILL cause increased wear)

(BTW I did a a search first but it didn't return much, and searching other forums just returned the usual 'I play Forza Motorsport therefore I know about suspension setup' drivel.)

Anything above -2.5 with toe in is going to wear excessively. You could probably run around -3 with zero toe and get minimal wear.

Camber does affect wear, but way less then toe. Best camber wear wise would be choose one according to how you drive. If you have most of tire thread wear on track (not by mileage of course, but by actual wear, which is much higher on track), wear will be less/more even with more camber. If you drive only on public streets within legal limits, it makes sense to run with less camber, as there you won't see that much side-Gs & tire side loading for it's sidewalls to flex much to need compensating with static camber. As for toe .. if it's not zero, car "drags" wheels all the time. The more the toe angle, the more dragging/wearing. Hence worth to go for minimized toe, while gains from it in handling are more then losses. My choice was zero toe front, and very slight toe-in (0.1dg) rear, for some extra self-stabilizing of RWD car in limited grip situations or to allow open throttle sooner when going out of curve.

Toe in will help with wear, it's toe OUT that causes problems with wear. I'm running -2.1 up front and -1.7 rear with some toe in and there's no extra wear at all. My last car was a Gencoupe and with -3 up front with minimal toe-in there was definite camber wear and it was A LOT worse when I had just a little toe-out.

Toe-out will kill a tire a lot faster than camber.

No, both toe-in and toe-out will rise wear. toe - means angled all the time tire against direction of travel, that slightly drags/slips all the time when moving. No matter if it's angled more to one or another side. What toe in-ness or out-ness direction changes is self-stabilizing or destabilizing of that car end where it's non zero, not wear extent. It's amount/width of toe angle that impacts wear, how much far from zero, where tires point in direction car moves, it is, that ups or lowers wear caused by toe. You can drag tire slightly to left or to right, it will wear more in both cases. One may add toe-out for planned _handling_ change, eg. to easier rotate rear or sharper turn in front (at expense of more nervous, less stable handling), tires will wear more. One may add toe-in and car will be harder to throw off balance and harder to rotate that end .. and tires will wear more.

In theory, sure. Now do it and see how the wear changes. In reality, a little tow out helps wear.

In reality car was too nervous with zero toe all corners in situations approaching grip limit (such as on track or in winter daily driving). Some slight toe-in rear helped. In reality i wouldn't wish to change suspension in a way to increase what i didn't like in first place :P. And are you really-really sure that wear differences were not of multiple of other variables and toe-out was really the only thing wear differences in your "real experience" should be attributed to, even more so to level of advising it to others? :)

A tire that is leaned over will want to move that direction due to what is called camber thrust. Slight toe out on a wheel with negative camber will counteract that and make the tire want to roll "straight" and reduce wear. The number I see in books is about 0.1 degrees of toe for every degree of camber.

However, there are other things going on, like deflection of suspension components/bushings/wheel bearings etc when the car is rolling. The drag from the front tires is generally going to push the toe out a bit, so what is set statically and what occurs when you are actually driving are two different things (conversely, the driven rear wheels are going to want to toe inward).

Plus of course the changes due to suspension travel. While bump steer is fairly minimal it is not exactly zero.

So yeah, in theory a little toe out should help wear especially with a good amount of camber. in reality setting toe to zero or slightly in tends to be more popular.

That's going to depend on how the car is being driven most of the time. If it sees mostly heavy cornering loads the wear will actually be better with more camber since it's not chewing up the outer shoulder of the tires as much. If it's just being driven on the highway, then your statement is pretty accurate.