A single lightweight engine capable of operating over a wide range of Mach numbers from startup to the hypersonic regime, which was proposed for aircars, aircrafts, and spaceships (Naitoh et al, 2010, 2011, 2012), has an impressive potential of low noise and high thermal efficiency. Its new compression principle is based on super multijets colliding with pulsation. Shocktube experiments and ... [Show full abstract] computational fluid dynamics with a chemical reaction model at about M=1 clarified the efficiency and stability of this engine system. In this report, computations for this engine system extended with a special twister piston show reduction of thermal loss and noise, even for low subsonic Mach number M< 0.3. Then, the present engine has a good affinity with ram-scram system, because the present engine does not include turbofan system at the engine center. Thus, we will also show computational results for M>2. We also confirmed combustion occurrence by performing primitive testes for two prototype engines.