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Cambered Tires Can Improve Fuel Economy
thecarchik writes with an excerpt from Green Car Reports: "We already know that it's possible to curb your fuel consumption just by having your tires properly inflated, or better yet, installing a set of low rolling-resistance tires, however, soon there may be an additional avenue to look at when picking the most fuel efficient rubber for your ride. The answer is the camber of your tires, more specifically, the negative camber. This is when the tops of your car's tires are angled inwards towards the chassis. Of course, there are negative effects too — namely increased tire wear and impaired ride quality — which is why production cars almost always have zero camber." The linked article, as well as the New York Times article from which it draws, describe a new tire which is designed to minimize those negative effects.
Perhaps you should get your shocks replaced....
In a pure theory aspect, less tire on the road, less rolling resistance.
Sigh, go and learn something you retard.
They dont, any competent and not class limited suspension design dynamically adjusts camers in corners to develop the desired cornering camber, while not causing issues in strange line.
A lot of moronic 'boy racers' like to think a ton of negative camber is the sign of a race car, mainly because some suspensions designs develop a lot of un-adjustable negative camber when cars are over-lowerd.. This of course is terrible for handling (but they like to think it is not.) but since those cars cannot have it adjusted out with spending real money....
And F1 most certainly does NOT run static negative camber, it would be a disaster for straight-line handling. They run DYANMIC camber in corners due to the uneven A arm suspension geometries.
I suggest you start here.
http://www.amazon.com/Competition-Car-Suspension-Construction-Motoring/dp/085429645X
http://books.sae.org/book-pt-90
Whether he needed it or not is debatable, but the points about different front/back tires and unidirectional tread are not snake oil.
Particularly in rear-wheel drive cars, it is not uncommon for the drive wheels (which need to apply torque) to be wider, while the steering wheels (which may need to cut through water/snow) are narrower.
Unidirectional tread is less common, but it does help reduce hydroplaning.
If you have just one of these, you can still move your tires in one direction (not full rotation, but front/back or side/side). If you have both, you have to keep your tires in the same location.
The same holds true for caster: toe the front wheels out a bit and the thing will wander all over the place; toe them in and the car will tend to center itself. Both of these also will tend to increase friction as well, which also it seems would negatively affect mileage. Given many cars nowdays run on low profile tires inflated to 40psi or more I have a hard time believing it's going to make much difference on a properly tuned and aligned vehicle, however.
I'm hoping you just mis-spoke here, or that you're not a suspension engineer. Caster and toe are completely different entities. Toe is whether your tires are pointed inward (toe-in) or outward (toe-out) when viewed from the top. Caster is a measurement of how far the center of the contact patch is behind the steering axis. Caster is what makes the wheel want to straighten out. Both toe and caster are much more important for straight line stability than camber is.