Originally Posted by
merlinextraligh
This simply does not comport with experience. A wider tire has to give more grip than a narrower one, ceterus peribus. Otherwise, why do they put wider tires on sports cars? Certainly the fact that a Corvette can pull over 1g on a skidpad with 340mm wide tires, while an economy car does .7g on 130mm wide tires is in part the result of the different size of the contact patch.
Are you suggesting that you could put tires half as wide on a Corvette, and expect the same skidpad numbers?
I'll take a stab at this. I think the calculations are correct from an physics standpoint. For this equation the assumption must be made that the materials themselves will withstand the force generated. However in the case of a rubber tire the frictional forces can be higher than the cohesive strength of the rubber compound.
High horsepower cars use soft rubber compounds with high coefficient-of-friction compounds that are easily abraded, hence the need for wider tires to reduce the force. I'm not an engineer, so I could be wrong, but I think this the essence of it.