The 10 test frame quartz tube, quartz tube, quartz rod, piston top.

测试架石英管，以及石英外管，石英活塞顶杆。

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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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It's for detection of engine speed, piston top dead center position, signal ignition and injection control in top dead center of each piston.

主要用来检测发动机转速，检测活塞上止点位置，包括检测用于控制点火的各缸上止点信号、顺序喷气的第一缸上止点信号。

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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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