Yeah i was thinking about the fact that

Force of friction = Normal force * coefficient of friction

and normal force = m*g

This would mean that a car with more mass would grip better. But i think that i have seen some autocross cars with stripped interior and i was wondering if there was something that would offset the added friction?

Maybe something like the added momentum(because mass is greater)?

Just wondering....

 

Racing isn't as simple as math equations. This is why so many companies spend millions trying to shave tenths of seconds off of their times. An object in motion tends to stay in motion due to inertia, so a heavy car going into a turn has more inertia pulling it in the initial direction it was going before the turn, more lateral Gs. Tire grip, center of gravity, tire roll, tire temp, road temp, dust on road, the list goes on and on of what effects this.

 

A tire's grip goes up with the load on the tire, but NOT linearly. So overall, less mass = better cornering force (more positive grip to weight ratio). Now aero loading is free since it doesn't create any additional mass (only load), which is why Indy cars and the like have such phenomenal grip at high speed.

 

the tires grab better on a heavy car, thats correct. but what would you rather have. a 2800 lb car that grips well or a 1800 lb car that doesnt, assuming they have the same engine.

friction works great off the line momentarily, but what you are fogeting is that friction force moves in the negative direction (against the direction the car is moving). thats why things stop when you give it a push, because of friction. more friction from the tires will slow you down. im really not sure how performance tires work, but i hope that cleared a little thought off your mind.

 

you have to think about the fact that inertia works against friction. put the same set of 16" volks on a stripped civic and a ford excursion full of mexicans and see who can turn a 90 degree turn at a higher speed.

 

A lighter car has less grip, but needs less grip to toss the lesser weight around. A heavier car has more grip, but it needs it to toss the extra bulk around (inertia/ momentum). In the end, according to the physics book, both cars should be able to pull the exact same g's around a corner. However, in this case the physics book is a little off...

This is correct.


[Modified by Lsos, 9:19 AM 12/14/2002]

 

sry but could you clarify this a little more please. I'm not sure what you mean. Do you mean that the graph of a tires grip vs the load on the tire is not linear?

BTW thanks for replies.

 

Lets say the load on a tire is 100lbs, and the frictional force is 100lbs. This tire will be able to corner at a maximum of 1g.

Increase the load to 200lbs, and the frictional force will only go up to, oh, say....180lbs, and not the 200lbs that the physics book will have you think. This tire wil only be able to corner at a maximum of .9gs.

I guess this effect is much greater when you start nearing the load limit of the tire.


[Modified by Lsos, 10:03 AM 12/14/2002]