Which tool(s) should be used to inspect a cylinder head for warpage?

To inspect a cylinder head for warpage effectively, using a straight edge along with a thickness gauge is the most comprehensive approach. The straight edge serves as a reference tool that helps identify any deviations or irregularities across the surface of the cylinder head. It should be placed across various points of the head to check for flatness; any gaps noticed underneath the straight edge will indicate warpage.

The thickness gauge then allows for precise measurement of any warpage that is detected. This combination ensures that not only are you visualizing the warpage but also quantifying it, which is essential for determining whether machining or replacement is necessary.

While other tools, such as a dial indicator or Plasti-gauge, can assist in different aspects of engine measurement and clearance checks, they do not provide the same level of direct correlation between visual and measurable warpage as the combination of a straight edge and thickness gauge.