wheel alignment versus ride resistance

[sierra4000]

Hi,
how significant toe and camber affect car straight ride resistance? (top speed for example)
what tire width and aspect ratio affect this all?
(of course racing tires )

again Thank You
Radek

 

[GregLocock]

definitely. Figure on your camber sidethrust stiffness is about 100 N/deg and your toe sidethrust stiffness is say 500 N/deg

You do the math.



Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[cibachrome]

As far as toe is concerned, your dynamics toe setting will be different than your static toe because of propulsion forces as well as aero lift and dive effects on ride height.

Wide wheels usually have more Fx drag and also measurable aero drag effects. Wheelhouse size (you have to fit the fat wheels in and steer them for FWD)) and wheel spider area (you have to cool the brakes, though) can be players, too. Even outside mirrors will affect your top speed if you are traveling in the aero domain.

A simple coast down test can help you sort out some of these effects (all except the tractive force effects).

 

[sierra4000]

Thank You,
I had owner, which fears use wider slick tires for top speed loss,
but he use almost 20mm!!! rear toe for getting stability (was extremely front assymetrical bumpsteer)
I think it can not be worse now

how effects during acceleration? (for different speed)
I think aero become more important at high speed

 

[CapriRacer]

First, the rolling resistance of a tire is not as affected by tire size as much as it is by the tread compound - by an order of magnitude.

Also, I think there is a reason why race cars ALL use as wide a tire as possible - and that is because the traction generated during cornering and acceleration more than offsets the loss of top speed.

 

[sierra4000]

Thank You very much!