I am building a very simple car game, and was trying to come up with some attributes for car part upgrades. I've come to the assumption that every suspension part, including but not limited to: shocks/springs/tires, contributes to the traction that the vehicle has. (springs/shocks contribute in the way of keeping the tire on the ground through body roll, dives and squats, and irregularities in the road). I wanted to create a very SIMPLE model, something that I could use so I could just plug in some numbers for my car parts. What I have so far is thus: three variables for car traction: mu = the coefficient of friction of what tire is on the car (better tires will have a higher coefficient downforce lbs = force pushing down on the car as a result of air moving over it at speed contact patch = the area of the contact patch of the tire. wider tires will have more of a contact patch, meaning more traction My goal is to try and CREATE a simple equation using these three variables ONLY, to represent how much traction a car will have at certain points in moving. Now, I know there are many many more variables to traction, but all I'm trying to do is a simple simulation in a flash game. For instance, if I buy a new set of tires that are wider and have a higher coefficient of friction, I will have a higher value for my Traction Force. Also, what is the unit of Traction?