A study of the effects of oxygenated alcohol/gasoline/diesel fuel blends on performance, combustion, and emission characteristics in conventional reciprocating engines is reported. On the one hand, in alcohol-gasoline blends, dual alcohols-gasoline blends have not yet been sufficiently proven as suitable alternatives to single alcohol-gasoline blends in engines as far as performance is concerned. On the other hand, n-butanoldiesel, although it has a better miscibility factor in diesel than methanol or ethanol, is limited with regard to extensive application in the diesel engines due to its low cetane number. Engine performance was compared using single alcohol-gasoline and dual alcohol-gasoline blends, where the dual blends were constrained to meet the vapor issues regarding fuels and regulations. The blends were selected in terms of a combination by volume of one being higher alcohol (n-butanol) and the other, lower alcohol (methanol). The engines used for this study included a single-cylinder and a four-cylinder, naturally aspirated, four-stroke spark ignition engines and a fourcylinder, four-stroke compression ignition turbocharged diesel engine. In the n-butanoldiesel studies, a comparison was made with other studies in order to determine how suitable n-butanol-diesel blends were across the biofuel family such as the biodieselethanol-diesel blends. The findings were as follows: The dual alcohols-gasoline blends performed better than the single alcohol-gasoline blends depending on certain compositional ratios of the alcohols in gasoline regardless of vapor pressure consideration. The n-butanol/diesel alcohol blend (B5, B10, and B20, where B5 represents 5% nbutanol and 95% diesel) significantly reduced the regulated emissions in a turbocharged engine compared to other studies using biodiesel-diesel blends. The significant decrease in NO x , CO emissions, and reduction of unburned hydrocarbons content using nbutanol/diesel fuel (DF) blends were found experimentally. The use of dual alcohol / © 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.© 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.gasoline blends was beneficial due to their shorter combustion duration in crank angles and their higher-energy content compared with single alcohol-gasoline blends. The nbutanol/diesel blend fired in the diesel engine showed a higher brake thermal efficiency and improved brake specific fuel consumption compared to the study by others where ethanol\diesel and methanol\diesel blends were used.