Tires: Wide tires vs.Narrow tires, pounds per square inch, road surface

Question
With a wide tire, it will have more surface area on the road and with a narrow tire, it will have more pounds per square inch on the road but less surface area. Now with the same horsepower and rpm's increased at the same rate, what tire would have less traction and slip easier at takeoff.      Thanks

Answer
Assuming that the tires have the same load carrying capacity:

The wider tire would have greater grip due to the larger area in contact with the road surface.  Unlike simple friction, tires get their grip by interacting with the road texture.  So the more the contact area the greater the grip.  

The other half of this is that due to the curvature of the tire (it is a circle after all), going wider develops more area faster than going larger in diameter.

Hope this helps.