Whats the advantage of wider wheels?
Whats the advantage of wider wheels?
From what im learning, a wider wheel will provide the same amount of traction as a thinner wheel, because its just spacing the contact patch out. If anything, traction is broken easier with a wider wheel, its a physics book im reading btw. Can someone explain the concept of wider tires advantages and disadvantages.
Lets say you have an 8'' wheel and a 7'' wheel. Both wearing 225 size tires. The 8'' wheel will have a more square, maybe even going inwards sidewall than the 7'' wheel which will have the sidewall more rounded and kind of hanging over the lip.
Something to do with transitions and breakaway, that I can't explain right now, have something to do with it.
I think the most significant advantage of wider wheels, is the ability to run much wider tires. And as we all know, wider=more grip
Something to do with transitions and breakaway, that I can't explain right now, have something to do with it.
I think the most significant advantage of wider wheels, is the ability to run much wider tires. And as we all know, wider=more grip
"It will have the same contact patch as the thinner wheel/tire...as long as the weight is the same."
exactly, this is why tire sizing(width) is less important than compound for grip. Take for example the acura NSX, an excellent handling car by any measure, ran a 225-50-16 rear tire. Not 'wide' by any strech of the imagination, yet still turned a nice .96g on the skidpad and a great slalom(sp?) speed.
what you really do with a wider tire is make the contact patch wider, instead of longer...which CAN help. It makes the tire itself a bit better at resisting lateral forces(think wide versus narrow stance), and since the contact patch is wider, it makes a higher percentage contact with road...
I'll explain:
think of a gap in the road surface, typically these run perpendiculat to the tires contact patch. in a narro tire, with a long contact patch, the gap in the road surface would take up more(percentage wise) of its contact patch than a wider tire. make sense?
so wider tires do provide some benifit, to a point. Wider tires usually come in stickier compounds, too. The compound and tread design has more to do with tire grip than the size.
hope that helps!also, just FYI the engineer behind the new 350Z chose its tire sizes because the patch would be longer than it was wide, for the vehicles dynamics work better with it that way
-chet
exactly, this is why tire sizing(width) is less important than compound for grip. Take for example the acura NSX, an excellent handling car by any measure, ran a 225-50-16 rear tire. Not 'wide' by any strech of the imagination, yet still turned a nice .96g on the skidpad and a great slalom(sp?) speed.
what you really do with a wider tire is make the contact patch wider, instead of longer...which CAN help. It makes the tire itself a bit better at resisting lateral forces(think wide versus narrow stance), and since the contact patch is wider, it makes a higher percentage contact with road...
I'll explain:
think of a gap in the road surface, typically these run perpendiculat to the tires contact patch. in a narro tire, with a long contact patch, the gap in the road surface would take up more(percentage wise) of its contact patch than a wider tire. make sense?
so wider tires do provide some benifit, to a point. Wider tires usually come in stickier compounds, too. The compound and tread design has more to do with tire grip than the size.
hope that helps!also, just FYI the engineer behind the new 350Z chose its tire sizes because the patch would be longer than it was wide, for the vehicles dynamics work better with it that way
-chet*shrug* Depends on the situation and vehicle dynamics I would think. Most drag tires are both tall(long) and wide..I've never really checked out the contact patch on them. I know for most road racing, the tires are pretty wide and stiff(for obvious reasons) but they';re usually thinner than you'd think
WE actually had a huge discussion of this a while ago, with mysefl, c-kwick, 240_keyy and a few others that I cant remember right now, it was about a 4 page long thread...
Its got pictures in it to help you out:)-chet
WE actually had a huge discussion of this a while ago, with mysefl, c-kwick, 240_keyy and a few others that I cant remember right now, it was about a 4 page long thread...
Its got pictures in it to help you out:)-chet
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Grant@tirerack
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Q45tech
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A great deal has to do with the surface area of the tire and the ability of the tire side wall to shed heat [soak it up and away from the tread [contact path] and radiate it into the air flow.
Performance rubber compounds want to see a narrow range 160-185F to achieve maximum friction.
Trig angle of tread sidewall relationship, and how, how much force is transfered to wheel and how much is used up frictionally flexing the sidewall.
Generally the optimum wheel width lets the tires last longer vs. just the minimum wheel width which distorts the sidewall away from ideal shape.
Would be interesting to see lateral siffness diagrams [graphs] on the same tire vs.differing wheel widths with identical loads.........my guess it a 10% low peak [vs slip angle] with the minimum vs ideal. Whether 0.5-1 degree [SA] is significant except in autocross is unknown.
Not sure if these tests have ever been done as in professional racing wheel sizes are speced the same for all cars.
Too wide would be a problem in bead strength clamping force.
Performance rubber compounds want to see a narrow range 160-185F to achieve maximum friction.
Trig angle of tread sidewall relationship, and how, how much force is transfered to wheel and how much is used up frictionally flexing the sidewall.
Generally the optimum wheel width lets the tires last longer vs. just the minimum wheel width which distorts the sidewall away from ideal shape.
Would be interesting to see lateral siffness diagrams [graphs] on the same tire vs.differing wheel widths with identical loads.........my guess it a 10% low peak [vs slip angle] with the minimum vs ideal. Whether 0.5-1 degree [SA] is significant except in autocross is unknown.
Not sure if these tests have ever been done as in professional racing wheel sizes are speced the same for all cars.
Too wide would be a problem in bead strength clamping force.
The F = uN relationship is a very rough generalisation that ignores a lot of factors, such as slip angle and shear. A tires coefficient of friction u is not constant, but decreases as slip angle increases. IIRC Q45 actually had a graph of this relationship in another thread. Anyways I believe a wider contact patch would help generate greater lateral force at lower slip angles, reducing tire deformation & heating losses, & increasing total available cornering force. However, it will also give out at lower slip angles, making it less forgiving.
Drag tires use a tall sidewall to take advantage of the momentum of the tire carcass to increase tractive force... From my understanding, drag rubber is flexable enough so that during launch, it gets wound up and slapped against the ground like wet dough, creating some pretty amazing acceleration g-forces.
Much of this is just heresay that sounded logical to me... so don't quote me!
Drag tires use a tall sidewall to take advantage of the momentum of the tire carcass to increase tractive force... From my understanding, drag rubber is flexable enough so that during launch, it gets wound up and slapped against the ground like wet dough, creating some pretty amazing acceleration g-forces.
Much of this is just heresay that sounded logical to me... so don't quote me!
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Grant@tirerack
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It never ceases to amaze me how many Camaro guys want drag radials for front and rear tires on the street. I try to explain to them they have very flexible sidewalls so they can 'hook up' in straight line runs but they are so soft that they corner like marshmallows. If you have ever seen slow motion films you can see the sidewalls at work. You can see the sidewall torque around the rim and the tread will bunch up in front of the rim. I'ts a beautiful thing on a pro-street car:firedevil