enum tcar
{
   tInfernus1,
   tInfernus2,
   tNRG1
}
new TCar[tcar];

stock BelongingCars(vehicleid)
{
   if(vehicleid == TCar[tInfernus1]) return 1;
   if(vehicleid == TCar[tInfernus2]) return 1;
   if(vehicleid == TCar[tNRG1]) return 1;
   return 0;
}

//OnGamemodeInIt

   TCar[tInfernus1] = CreateVehicle.....
   TCar[tInfernus2] = CreateVehicle.....
   TCar[tNRG1] = CreateVehicle.....

//OnPlayerState Change

   if(newstate = PLAYER_STATE_DRIVER)
   {
      new vehicleid = GetPlayerVehicleID(playerid);
      if(BelongingCars(vehicleid) && PlayerIsNotWhat?)
      {
      new Float:x, Float:y, Float:z;
      GetPlayerPos(playerid, x, y, z);
      SetPlayerPos(playerid, x, y, z+3);
      SendClientMessage(playerid, 0xFF0000AA, "You can't drive this vehicle");
      return 0; 
      }
   }

new TeamRedVehicle[3]; //vehicle count is 3 for each team
new TeamBlueVehicle[3];
new bool:TeamRed[MAX_PLAYERS]; //Setting teams
new bool:TeamBlue[MAX_PLAYERS];

//OnGameModeInit
TeamRedVehicle[0] = CreateVehicle... // creating vehicles
TeamRedVehicle[1] = CreateVehicle...
TeamRedVehicle[2] = CreateVehicle...
TeamBlueVehicle[0] = CreateVehicle...
TeamBlueVehicle[1] = CreateVehicle...
TeamBlueVehicle[2] = CreateVehicle...

//OnPlayerConnect
TeamRed[playerid] = true;
//or
TeamBlue[playerid] = true;

//OnPlayerDisconnect
TeamRed[playerid] = false;
TeamBlue[playerid] = false;

//OnPlayerEnterVehicle
if(TeamRed[playerid])
{
    for(new i=0; i<MAX_PLAYERS; i++)
    {
        if(vehicleid == TeamBlueVehicle[i]) return ClearAnimations(playerid, true);
    }
}

if(TeamBlue[playerid])
{
    for(new i=0; i<MAX_PLAYERS; i++)
    {
        if(vehicleid == TeamRedVehicle[i]) return ClearAnimations(playerid, true);
    }
}