Alternative fuels have an important role to play for both spark ignition and compression ignition engines, the prime reasons being the need to trim down the dependency on gasoline as a fuel and its economic aspects. Many investigations have primarily focused on using alternative fuels to see the diminishing effect on fuel consumption. The aim of this review is to study and analyze the range of opportunities and future prospects of introducing blends of gasoline +/-ethanol, gasoline with all other alcohols derivative and subsequent alternative fuels in varying percentage ratios in the existing spark ignition engines by diagnosing various aspects such as air-fuel ratio, operating cylinder pressure, ignition timing and compression ratio related to the performance parameters only. Ethanol blends in lower proportions showed an increment in the range of 2.31 +/- 4.16% for the engine torque and 0.29 +/- 4.77% for brake power. Brake specific fuel consumption (BSFC) increased for higher volume of ethanol content in the range of 5.17 +/- 56%. Brake thermal efficiency (BTE) was slightly on a higher side in the range of 2.5 +/- 6% when ethanol +/-gasoline blend was used.