WheelCollider - real friction values

Hi. I'm trying to create a racing game with a little bit realistic physics. I'm using WheelCollider and Rigidbody physics.

For calculation motor torque I'm using this code:

     // CALC CURRENTLY ENGINE RPM
     rpmEngine = ( rpmMin + (wheelFrontLeft.rpm * gearsRatio[currentGear] * wheelDifferential));
     
     
     // CALC FINAL MOTOR TORQUE
     // I take the car torque from the table according to the EngineRPM
     motorTorque = (torqueByRpm[TorgueByRpm(rpmEngine, rpmStep)] * gearsRatio[currentGear] * transEfficiency * wheelDifferential )
 * Input.GetAxis("Vertical");

Then I send "motorTorque" to Wheel Colliders.

My question is. What values ​​set to WheelColliders friction to accomplish this ideal behavior ?

Because the default values aren't very realistic. Thanks.