Tyre roll when cornering?

[amigamemory]

Hi all
im reading some technical stuff about f1 cars and how they work etc I came across an article saying:
"Increasing tyre pressure can reduce tyre roll"

I dont quite understand this statement, surely increasing pressure would reduce the contact patch
and a small contact patch should yield in more roll?

Tyre roll is it the same as sliding when cornering ie understeering?

Please help

[marcush.]

simply spoken the tyre will squash/deform less when more inflated ,more so when force is applied as in cornering the tyre will deflect less ,and so the effective rollangle (tyre deformation+ suspension induced roll) will be less.
This is of course a big factor just because of the high sidewalls in F1 .

[amigamemory]

Thanks for replying, Ah yes that makes sense so higher pressure can reduce tire roll in cornering by making the tire stiffer and less pliable ie stop lateral sliding.

Anyone know how the tyre pressures can be used to fight understeering and oversteering?

[marcush.]

Thanks for replying, Ah yes that makes sense so higher pressure can reduce tire roll in cornering by making the tire stiffer and less pliable ie stop lateral sliding.

Anyone know how the tyre pressures can be used to fight understeering and oversteering?

the basic point is there is no adjustment of more pressure = o/s
You have to understand that for any given situation there is a optimum tyre pressure ,wich is dependant on the loads applied to the tyre.
from this optimum pressure ,which leeds to the optimesd inflated shape (maximising
contact patch size and shape)you will find that increasing or decreasing pressure will lead to a loss in performance or actually lead to catastrophic failure due to
overloading and destroying the tyre carcass.
some tyres especially high downforce sportscartyre a not very sensitive to pressure adjustments becuase they have to have a very stiff carcass ,in these cases to try to make balance adjustments with pressure is not working at all .

[Giblet]

This is a great basic setup guide (half oval, half road) that explains all the basics, and what the basic adjustments will do.

It was made for the sim iRacing, but it is all compiled from real world knowledge and is a great document.

Setup Guide PDF

[amigamemory]

Thankyou very much doc looks really interesting.

cheers

[Jersey Tom]

In terms of balance changes, adjust tire pressure just like you'd adjust springs. Big swings in air pressure will be enough to change limit grip capacity.. but small changes of maybe < 1 psi are enough to change tire and suspension rates.

[ubrben]

Hi all
im reading some technical stuff about f1 cars and how they work etc I came across an article saying:
"Increasing tyre pressure can reduce tyre roll"

I dont quite understand this statement, surely increasing pressure would reduce the contact patch
and a small contact patch should yield in more roll?

Tyre roll is it the same as sliding when cornering ie understeering?

Please help

You're really overthinking this.

If the tyre pressure is higher, the spring rate is higher, and the roll stiffness is therefore higher and the car rolls less.

Ben

[DaveKillens]

I believe the original problem could be defined as "lateral tire deformation". A tire is just a bag of air, and it's shape can be influenced by many factors.

When a car is cornering, the tire is attempting to deal with the immense forces pushing sideways. Where the tire meets the road, it deforms.



On the left picture, it illustrates how the tire is being forced out of it's inflated shape by cornering loads. Obviously, one fix is just to add pressure.

But since a tire has a very difficult job, and it is in a constant state of deformation, a solution is never that simple.

[gambler]

Im not sure the word for it, but theres a certain amount
of "torque wrap up" under accel and deccel. I dont know if
that affects the lateral roll out.

[gambler]

could it be that as speed increases the centrifugal force
makes the tire stand up a little more in the corner.
(just thinking out loud)