void _add_tire()
{
 while(you)
 {
   VECTOR _p, _a;
 // simple connection without bones or vertex (fixed pos)
   vec_set(my.x,   you.x);
   vec_set(my.pan, you.pan);
 // or add bones at your car body, where the tire(s) should
 // be placed and use this
    vec_for_bone(_p, you, "TirePos1");
    ang_for_bone(_a, you, "TirePos1");
   // or place a vertex at the pos where the tire(s) should be placed
   vec_for_vertex(_p, you, 123); // Vertex 123

   vec_set(my.x, _p);
 //vec_set(my.pan, _a);
  wait(1);
 }
 // car body lost ?
 ptr_remove(me);
}
action MyCar()
{
 ent_create("tire.mdl", vector(my.x, my.y, my.z), _add_tire);
// ent_create("tire.mdl", vector(my.x, my.y, my.z), _add_tire2);
// ent....
// ent...

 while(1)
 {
   // your car code
  wait(1);
 } 
}