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Internal combustion engine popularity has been won commercially by the four-stroke type engine surpassing the two-stroke and rotary wankel engines in the world market places. Commercial engines both gasoline and diesel fuels are mostly using the four-stroke principle and even the hybrid cars still rely on this type of engine as their backup source of power. Current research in this areas are optimizing the effectiveness of the four-stroke combustion engine related to fuel consumption, fuel-air mixture, reuse of exhaust energy to feed air inflow, fuel control system to feed exact volume of fuel, exact firing time using intelligent control unit and lower hydrocarbon emissions. However, the development in the engine power output generation is limited due to nearly satisfied expectation of the automotive users caused by limited road development; meanwhile, the short range aerospace engine technology has limited attention in the advanced countries but certainly not in the archipelago country such as Indonesia. This paper is classified to initiates first publication from series of research log book on a new engine design that promotes double power output principle called Double Power Ecological Engine (DPE) for power drive vehicles. The design of DPE engine is located in the firing order, which has direct influence to the new design configuration of crank shaft, air inlet, exhaust and the piston head geometry. The ultimate design of this combustion engine is secured under the firing orders, which are made to secure power output twice as much as it is in the four-stroke engine so that double potential power engine is promoted under ecological fuel ethanol. The design of DPE engine of this research is expected to generate 280 kW power output based on the 1.4 liter engine, which commercially generate around 141 kW. Further research will show the effectiveness of the DPE engine design leading to commercial application.

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The seal face is the main component of a mechanical seal to prevent leakage in a system with fluid flow. Seal face manufacture is generally produced by the material removal process, which causes some raw material waste. Powder metallurgy is the process of manufacturing products from metal powders with raw material efficiency of up to 97%. This study discusses the relationship between the manufacturing process parameters of seal face with SiC material through a powder metallurgy process as a substitute for manufacturing by material removal. The approach used in this research was the design of experiments with the Taguchi method and the technique of Gray Relational Analysis. Process parameters controlled were compaction pressure (CF), compaction time (CH), sintering temperature (ST), and sintering time (SH). Responses were measured in the form of surface hardness (HV) and density. The combination of process parameters that produces the optimum response is CF = 408 N/mm 2 (level 3), CH = 2 min (level 1), ST = 1050 • C (level 3), SH = 120 min (level 2) with contribution of process parameters CF = 38.06%, CH = 2.53%, ST = 49.50%, and SH = 9.91%. The optimum surface hardness and density values were 513.03 HV and 3.04 gr/mm 3 .