Speedhack with ALT-Key

public OnPlayerKeyStateChange(playerid, newkeys, oldkeys)
{
   if(IsPlayerInAnyVehicle(playerid))
    {
       if(newkeys == KEY_FIRE)
      {
          new Float:vX, Float:vY, Float:vZ, Float:vA;
          new myCar = GetPlayerVehicleID(playerid);
         GetVehicleZAngle(myCar, vA);
         GetVehicleVelocity(myCar,vX,vY, vZ);
         SetVehicleVelocity(myCar, vX+=0.20 * floatsin(-vA, degrees), vY+=0.20 * floatcos(-vA, degrees), vZ);
      }
   }
}