Biodiesel from non-edible vegetable oil is considered as a monetarily doable source among the conceivable sources. It can be used as a replacement of the fossil diesel without any modification of engine design. In this study, "Millettia pinnata" (MP) which is known as Karanja and "Croton megalocarpus" (CM), non-edible biodiesel feedstock sources used for biodiesel production. 20% (v/v) of each M. pinnata (MP20) and C megalocarpus (CM20) and their combined blends were evaluated in a single cylinder diesel engine with variable load and speed condition in the context of performance, combustion and emission characteristics. For speed test condition, MP20 and CM20 reduced the brake power by 3.70% and 0.53%, brake thermal efficiency by 3.36% and 1.41%, carbon dioxide emission by 18.46% and 6.20%, hydrocarbon emission by 9.00% and 2.89% respectively compared to neat diesel but increased the brake specific fuel consumption by 7.63% and 4.64%, NOX emission by 17.15% and 8.16%, respectively. Beyond diesel, a mixture of 5% MP and 15% CM biodiesel with 80% diesel (MP5CM15) provides higher in cylinder peak pressure (77.44 bar), better heat release rate (39.26 J/degrees CA), shorter ignition delay and combustion duration. Thus MP5CM15 found to be a substitutable alternative to neat diesel except for NOX emission. (C) 2017 Elsevier Ltd. All rights reserved.