Valve stem to guide clearance..
 

I have been told of a special tool to check the guide to stem clearance on cylinder heads. Instead of the "old" method of setting a dial indicator up so you can see the "rock" between the stem and guide, this tool offers a closer measurement. The tool is like a dial indicator that will "slip into" the guide, with slight interference fit, and gives you the ID of the guide, then you just measure the OD of the valve stem with a micrometer and subtract. I did not know about this method and would like to know if anybody uses it or have I been given incorrect information.

never heard of it. i always use the dial indicator method and im sure that the dial indicator method is more than sufficient... the guide either needs to be replace or it doesn't

Dial bore gage.

Sure, it's called a dial bore gauge.
It's just a real small one!

Ron

Dial bore gauge is the way to go. It's more accurate than measuring the "rock" of the valve.

Goodson tools sells the Sunnun setup, it's pricey though.