Joe,
My RS4 running RLI Biosyn went through 1.5 quarts in 10K miles on one run, and 3/4 quarts in 5K miles on another. The 10K run had 4 days of track time, over two weekends at Watkins Glen and Mont Tremblant, with the engine at full throttle for a total of 6 hours.
The engine fuel dilutes like crazy (1.5% to 3%) and carries away oil with the fuel. In some cases, with some oils, the oil level remains constant, because the oil is exchanged with fuel. I saw that with Motul 8100 Etech 0W-40, as viscosity dropped like a stone.
My RS4 running RLI Biosyn went through 1.5 quarts in 10K miles on one run, and 3/4 quarts in 5K miles on another. The 10K run had 4 days of track time, over two weekends at Watkins Glen and Mont Tremblant, with the engine at full throttle for a total of 6 hours.
The engine fuel dilutes like crazy (1.5% to 3%) and carries away oil with the fuel. In some cases, with some oils, the oil level remains constant, because the oil is exchanged with fuel. I saw that with Motul 8100 Etech 0W-40, as viscosity dropped like a stone.