| 摘要 |
PURPOSE:To improve flow amount balance as well as total flow amount coefficient by a method wherein the path of exhaust gas, connected to the seats of respective exhaust ports, are chocked in the same range of ratio while the path of exhaust gas from a joining part to a flange of the exhaust gas side is expanded in smooth. CONSTITUTION:The paths 5, 6 of exhaust gas, having necessary sizes, are provided after respective seats 3, 4 of two exhaust valves 1, 2 and both of the paths 5, 6 are joined on the way at a place A, and thereafter, they arrive at the flange B of the exhaust gas side as one path 7 of the exhaust gas. In this case, the exhaust gas paths 5, 6, from respective seats 3, 4 at respective exhaust ports RL, PS to the joining part A, are formed so that the sectional area of the exhaust gas paths 5, 6, orthogonal to the center lines of the exhaust gas paths 5, 6, become 50-60% of the area of the exhaust valves 1, 2 at the valve heads thereof. The path 7 of the exhaust gas is formed so as to have a smoothly expanded configuration. According to this method, the flow amount balance as well as the total flow amount coefficient may be improved. |
