Innovative Cambered Tire Helps Saves Fuel, Boost Handling

[Frank Lee]

Innovative Cambered Tire Helps Saves Fuel, Boost Handling - Green Car Reports

Innovative CamberTire

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.

Racing cars typically feature negative cambered tires as they improve grip when cornering due to the tire being at a more optimal angle to the road, transmitting the forces through the vertical plane of the tire, rather than through a shear force across it. Another benefit is the increase contact area with the road, also when cornering.

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. However, a car enthusiast by the name of John Scott has devised a special tire dubbed the CamberTire that is claimed to negate the increase wear and ride penalties normally associated with cambered tires.

Scott first got the idea after seeing a heavily laden Lexus vehicle with its rear tires steeply cambered. In 1999 he filed a patent for a “tire with a constantly decreasing diameter” and the CamberTire was born. Prototypes of Scott’s CamberTire on a Mitsubishi Lancer Evolution GSR test vehicle have shown to have shorter stopping distances, higher cornering speeds, improved ride and even improved fuel economy.

The key to his design is an asymmetrical tire mold that yields an outer sidewall slightly taller than the inner sidewall. The wheel alignment must be adjusted to provide at least three degrees of negative camber.

Scott is now working closely with a number of firms, including motorsports tire distributor M&H Racemaster, to further develop the CamberTire.

I am going to need a good drug induced trip to understand this one...

I understand Kaz w/o tripping tho'.

[EdKiefer]

well if the vehicle has such negative camber it would scrub a lot less and save fuel/drag. But I don't think they mean change your camber on your stock vehicle and add these tires and you improved FE , handling yes IMO .

Also 3 deg is a lot of camber . You start to notice the lean on cars around past 1deg .

[ChrstphrR]

Interesting find there Frank.

It doesn't seem all that intuitive, until you think about what actually goes on with a tire while the car's rolling -- and going through turns.

Even if you're not charging a turn, at normal road speeds, you still have weight transfer, and body roll. That changes the position of the tires relative to the road, tilting them away from the ideal almost upright orientation that'll give them a consistant, even contact patch with the road.

After all, it's those dynamic changes -- the forces of the car acting on the suspension and tires, that make for most all of the seemingly counterintuitive suspension setups. If body roll and loading up different corners of the suspension didn't occur going through turns (i.e. ignoring the laws of physics), we wouldn't even have any oddball setups with the weird slants and tilts with camber, caster, toe. We'd just have neutral zeros for all measures, and it'd be ideal at any speed -- just like Unicorns are set up for race day!

That said, I'll reserve judgement on this conical-tire idea yet until I see more information (tests, objective reviews with *tests*, maybe some ... tests) on this one.

[Allch Chcar]

Not a new invention just in the works for a couple years. Looking forward to some test results! Excessive Camber may not be good for understeer that Daily Drivers may like but for performance vehicles it could become a common tire.

[Frank Lee]

Yeah, if there are any vehicles out there that spend more time turning than going straight, this might have something...

[gone-ot]

..Cop cars?

[Frank Lee]

Naaaah, don't think so.

[EdKiefer]

The problem I see is it would depend on suspension geometry .
A vehicle with MacPherson struts the camber stays the same basically with wheel deflection but a vehicle with double A arms camber changes according to depression in that corner .

[Allch Chcar]

Drift racing! I actually scrubbed the outside of my front tires .

[mwebb]

Originally Posted by EdKiefer

The problem I see is it would depend on suspension geometry .
A vehicle with MacPherson struts the camber stays the same basically with wheel deflection but a vehicle with double A arms camber changes according to depression in that corner .

camber changes on single link suspensions
( macphearson strut )
and remains relatively constant on multi link suspensions ....

either way -
a consistent
3 degrees of negative camber is going to change the loading on the wheel bearing
there will be wheel bearing failure problems as a direct result.
imho