Finding top dead center of an engine can be a pretty easy job if you have the right tool. Well this is the right tool. The S&S Top Dead Center Tools make it easy to find exact top dead center of any engine. This is the best way to calibrate your degree wheel when dialing in cams or performing any of a number of checks and modifications based on the position of the crankshaft. When you need to know for sure, you need the S&S TDC tool. Fits engines with 14mm sparkplug holes. S&S Part #: 53-0321