This study aimed to appraise the use of gasoline-methanol-ethanol-isopropanol quaternary fuel blends at 7 and 8.5 compression ratios in an air-cooled, spark-ignition single-cylinder engine under motor loads of 1.5, 2.5, 3.5, and 4.5 Nm at a constant speed of 2500 rpm through energy, exergy, sustainability, and economic analyses. Fuels MEP12 (Methanol 4 %+Ethanol 4 %+Isopropanol 4 %+Gasoline 88 %), MEP21 (Methanol 7 %+Ethanol 7 %+Isopropanol 7 %+Gasoline 79 %) and MEP30 (Methanol 10 %+Ethanol 10 %+Isopropanol 10 %+Gasoline 70 %) obtained by mixing ethanol, methanol, and isopropanol alcohols with gasoline in various ratios were scrutinized on the point of performance and emissions. Using the data obtained, energy and exergy analyses were performed, and the thermal and exergy efficiencies were calculated. The uppermost thermal efficiency was 22.25 % for MEP0 fuel at 8.5 compression ratio at 4.5 Nm engine load and the preeminent exergy efficiency was 20.72 % for MEP0 fuel at 8.5 compression ratio at 4.5 Nm engine load. Among all fuels, the lowest CO emissions, at 2.63 g/kWh, were achieved with the MEP30 fuel at a compression ratio of 8.5 and a motor load of 1.5 Nm. The lowest gases of HC, at 0.34 g/kWh, were recorded with the MEP30 fuel at a compression ratio of 8.5 and a motor load of 2.5 Nm. The lowest CO<inf>2</inf> emissions (g/kWh) were observed with the MEP0 fuel at a compression ratio of 7 and a motor load of 4.5 Nm. The MEP30 fuel appears to be a viable surrogate propellant for use in spark-ignition engines due to its ability to reduce emissions.