Dry sump oil systems were once found only on racing engines, but they are starting to find their way into more production cars, like the LS 7 and Mercedes-Benz V8. Also, many prototype engines for fuel-efficient cars now have dry sump oil systems. Why?
Packaging: No oil pan means the engine can sit lower. This gives a car a lower center of gravity and potentially better aerodynamics. Also, the oil tank can be mounted in a variety of locations under the hood.
Power: Since there is no oil sloshing around below the crank, more power can be generated. More power also means more efficiency and better fuel economy using a dry sump system.
Engine Wear & Startup Emissions: Pumping cold oil through an engine does the most damage to a bearing, and an engine is the dirtiest during the first 30-60 seconds of running. Storing oil in a thermos-type device in the oil tank can use warm oil instead of cold oil at startup, which will lower emissions. A dry sump can also carry more oil so change intervals can be extended even longer.