piston top

基本解释

Piston top lands are machined to piston manufacturer's specifications.
根据制造厂家说明书要求重新加工活塞环。
Moreover, the ball plungers (6) are positioned near the piston top dead center, at which the piston ring is positioned.
另外，球塞（6）设置在靠近活塞上死点的活塞环所在的部位。
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The piston top eccentricity and transverse velocity peak value are enlarged by 23% and 22% in the improved design, respectively, which increase the possibility of scraping cylinder.
结果表明：进行上述改进设计后，活塞顶部横向偏移的幅值增加了23%，活塞横向运动速度的峰值增加了22%，增大了擦缸的可能性；

Instead of sparking the ignition when the piston is close to top dead center (when the air is compressed), that spark occurs as the piston is pulling away, when the air pressure is at its most turbulent, creating much faster ignition and more power.
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