The acceleration required for an object to navigate a circular locus is given by a = v^2/r where a is the acceleration, v is the tangential velocity and r is the radius of curvature of the path. Now, to find the Force required to move an object within this circular path, we multiply the acceleration by the mass of the object, so F = (m * v^2) /r All good. This is, to repeat, the force required to go in the circular path. The last thing you'll need is to know what force the tyres can yield on the road. This calculated theoretically, by the formula f = uN where f is the resulting frictional force, u is the friction coefficient between two mating surfaces, and N is the Normal reactionary force between the two surfaces due to the gravitational pull on the car. The value of u can be found in some data books, and varies with tyre condition, road condition, material, oil, water, etc. N can be increased by the addition of a spoiler, u by buying better tyres. Once you've calculated the available frictional force for one tyre, multiply it by four for a car (four tyres, assumed equally responsive) and that will give the overall force available. You can now use this figure to compare with the force required. If the frictional force is less than the required force, you'll slide, else you probably won't. Don't forget to include a "Safety Factor" in your calculation to account for unknown and unrealised variables.