[Roger Jackman]

I have not done my first race with SRS yet, but am really looking forward to an AC DTM race (BMW or Merc). I understand that restrictors, ballast and fuel are not the same between series cars, so I would like some basic idea of what to plan for in a pit stop. Will anyone share approximately how much fuel a BMW and Merc will need? Are tire changes required/advised? I have not even had to pit in AC yet, and would like to try a few dry runs before getting in everyone's way. Again, not looking for anyone's strategy secrets, just answers in general terms is all I need. Any help is appreciated. 
Thanks.