Kajian Eksperimental Pengaruh Etanol Pada Premium Terhadap Karakteristik Pembakaran Kondisi Atmosferik Dan Bertekanan Di Motor Otto Silinder Tunggal Sistem Injeksi = Experimental Study of The Influence of Ethanol-Premium Blends on Combustion Characteristics at Atmospheric Condition And Pressurized in a Single Cylinder Spark Ignition Engine.