Draining the oil in a Dry Sump System
To change oil in a Dry Sump System, the oil should first be still warm from running. Dry sumps differ from standard wet sump systems in that the majority of the engines oil is stored in the Dry Sump tank. However, there will still be oil in the pan, lines and filter.
1) ARE dry sump oil tanks have a threaded "O" ring plug in the very bottom of the tank, under the cone shaped bottom. Remove this plug to drain the majority of the oil. If you can not get to the bottom drain plug, the oil can be ( mostly) drained by un screwing the line hose end that is connected to the oil supply fitting on rear bottom of the dry sump pump pressure stage. (ARE pumps) or in the case of scavenge only systems, from the fitting in the pan that supplies the internal oil pump. This line can then be allowed to hang down below the tank bottom and drain. Most of the oil will be syphoned out, as although the fitting is on the lower side of the tank, ARE tanks have an internal tube going to the bottom.
2) ARE dry sumps have integral screen filters built into the scavenge fittings in the pan, which help protect the scavenge stages on the dry sump pump from any large particles in the oil. These should be removed to check the screens for debris. At the same time, this will allow the oil that remains in the engine and pan to drain.
3) The rest of the lines and oil cooler can be drained the same way.
4) The spin on oil filter will also be changed at this time, and lines drained if needed. . The new oil filter should be filled with your new oil before installing. This allows the engine to get pressurized oil sooner, without having to fill the filter too.
Keep in mind that if this is a normal maintenance or "after every race" oil change, and there is no debris in the oil, or reason to think there might be, you do not have to drain all the lines unless you want to. The tank, pan, filter and cooler should evacuate the majority of the oil, and if relatively clean will merge fine with the new oil.
Note: this is totally a matter of choice and not a recommendation
After the oil change, follow the normal "tank filling and oil level" instructions