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TDC Whistle

Top Dead Center Whistle

TDC WhistleDevice that whistles when a piston reaches Top Dead Center.

How to use a TDC Whistle:

Top Dead Center WhistleWhistle that screws into a spark plug hole to tell when the piston is at top dead center (TDC). Especially useful because it works for all the cylinders not just #1.
Top Dead Center Whistle as seen in Basic Engine Building:

TDC Whistle used to find TDC on a SB Chevy 350Here we have our TDC Whistle screwed into the spark plug hole of our cylinder #1. As we turn the crank, the air rushing out of the hole will cause the tip to whistle as the piston reaches TDC inside the cylinder.
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