Abstract: Provided are oil reservoirs and engine oil circulation systems including an upper sump capable of receiving oil from an engine, a lower sump disposed vertically below the upper sump, a valve-controlled orifice (VCO) penetrating the upper sum bottom, an oil chimney capable of receiving oil and communicating oil to the lower sump, and an oil conduit capable of extracting oil from the lower sump. Methods for operating systems include maintaining the VCO in an open position for a draw down duration temporally proximate an engine cold start, subsequently circulating oil between the engine and the oil reservoir, actuating the VCO to a closed position subsequent to the draw down duration for a warmup duration, and actuating the VCO to an open position subsequent to the warmup duration. Methods can further include actuating the VCO to an open position during the warmup duration in response to an increased oil demand event.

Abstract: An engine variable compression ratio arrangement can be equipped in an internal combustion engine. The engine variable compression ratio arrangement includes a planetary gear set. The planetary gear set receives rotational drive input from an engine crankshaft, and the planetary gear set transmits rotational drive output to an eccentric shaft. The rotational position of the eccentric shaft is shifted relative to the rotational position of the engine crankshaft by way of the planetary gear set. This shifting varies the compression ratio of the internal combustion engine.

Abstract: Provided are oil reservoirs and engine oil circulation systems including an upper sump capable of receiving oil from an engine, a lower sump disposed vertically below the upper sump, a valve-controlled orifice (VCO) penetrating the upper sum bottom, an oil chimney capable of receiving oil and communicating oil to the lower sump, and an oil conduit capable of extracting oil from the lower sump. Methods for operating systems include maintaining the VCO in an open position for a draw down duration temporally proximate an engine cold start, subsequently circulating oil between the engine and the oil reservoir, actuating the VCO to a closed position subsequent to the draw down duration for a warmup duration, and actuating the VCO to an open position subsequent to the warmup duration. Methods can further include actuating the VCO to an open position during the warmup duration in response to an increased oil demand event.