Diesel-ignited propane dual fuel low temperature combustion was characterized in a singlecylinder research engine (SCRE) at constant values of indicated mean effective pressure (IMEP of 5.1 bar), engine speed (1500 rpm), and propane energy substitution (PES = 80%). The effects of three important engine parameters (start of injection (SOI) of diesel fuel, common-rail pressure (Prail) for diesel injection, and boost pressure (Pin)) on engine performance, combustion, and emissions were examined. As SOI was advanced from 355 absolute crank angle degrees (CAD) (or 5° BTDC) to 280 CAD for constant Prail = 500 bar and Pin = 1.5 bar, the apparent heat release rate (AHRR) profiles changed from a two-stage, "diesel-like" combustion process to a smooth, "Gaussian-like," single-stage combustion process, that was representative of more homogeneous combustion. In addition, with SOI advancement, the combustion phasing (CA50) was initially advanced but eventually occurred later for very early SOIs. Indicated-specific emissions of oxides of nitrogen (ISNOx) were reduced to about 0.12 g/kWh for SOIs advanced beyond 310 CAD while maintaining high indicated fuel conversion efficiencies (IFCEs). While smoke emissions were below 0.1 FSN for all conditions tested in this study, indicated-specific hydrocarbon (ISHC) and