(一)众所周知,侧置气门汽油机有其固有的缺点,具体表现为:燃烧室不紧凑,面容比大;火焰传播距离长,机械辛烷值低,不利于提高压缩比;进气气流急转弯,气门尺寸受限制,充气性能较差等。这些因素是侧置气门汽油机的性能指标一般不如顶置气门汽油机的内在原因,也是人们对侧置气门汽油机的普遍看法,而且认为难以改进,就是传 (A) As we all know, side valve gasoline engine has its inherent shortcomings, the specific performance: the combustion chamber is not compact, large face ratio; flame propagation distance, low mechanical octane, is not conducive to improving the compression ratio; intake flow sharp turn , Valve size is limited, inflatable poor performance. These factors are side-valve gasoline engine performance is generally not as good as overhead valve gasoline engine is the internal reasons, but also people on the common side-valve gasoline engine, and that it is difficult to improve, that is,