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Better Tyres Or Wider Tyres?

lastlineofdefence
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J_Red33 Experienced

J_Red33

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Posted (edited)
the contact patch thing is a myth. force is pressure times area, and the pressure a tyre can exert on the road is equal to its internal air pressure. therefore no matter what shape of tyre (wide or skinny) you will have the SAME area on the road.

However, a wider tyre will have a wider patch and a skinny tyre will have a longer patch. wider patch is better for cornering grip, skinnier patch is better for driving in the wet as there is less water to push out of the way.

There's a trick with this when it comes to using a wider tyre & that is to use a slightly lower air pressure in the tyre. This way the contact patch is expanded sideways while giving roughly the same contact length as the skinnier tyre. Overall you should end up with a lot more surface area.

This theory is also very dependant on what kind of profile your tyre has. A lower profile tyre would generally stay a bit rounder than a higher profile one hence drag cars have very high profile tyres on the rear in relation to cars that have to corner too.

For 2 tyres of the same rim diameter & sidewall height, I think you will find the difference long ways to be negligable in comparison to the gain you get from going to a wider tyre & wheel when keeping the type of tyre the same.

Edited by JazzaR33
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mokompri Community Regular

mokompri

Posted
Posted
the contact patch thing is a myth. force is pressure times area, and the pressure a tyre can exert on the road is equal to its internal air pressure. therefore no matter what shape of tyre (wide or skinny) you will have the SAME area on the road.

However, a wider tyre will have a wider patch and a skinny tyre will have a longer patch. wider patch is better for cornering grip, skinnier patch is better for driving in the wet as there is less water to push out of the way.

actually what your saying is a myth. if we were talking about a balloon which deformed proportionally to the amount of force applied to it, then yes this would apply. but when you have a tyre with stiff sidewalls, the deformation is no where near proportional, and so size of the contact patch does vary.

  • 3 weeks later...
GTshortie Proficient

GTshortie

Posted
Posted

Alright Guys...

last night headed down to WSID with my STOCK r33 rims 205/55/r16 wrapped with TOYO T1R's and guess what?!.

2.082 60ft with 32psi tyre pressure.

previously was running Dunlop Formula RSV 98Spec 255/40/r17 and got best of 2.382 60ft with varying tyre pressures. and consistent 2.4-2.5 60ft.

LAST NIGHT very first run 13.640 from a previous PB of 14flat with a 2.133 60ft then consistent 2.1-2.2 60ft's the whole night.

Sooo HAPPY!!.. thats it gonna aim for a 1.999 60ft with 205/55/r16 toyo tyres now!

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