Head Re-torgueing - Hot or Cold?

[Ron/IA]

I have been reading with interest the discussion on torqueing the Model A head in the post titled - "hmmm...wet head stud".

The majority consensus is that re-torqueing the A head should be done after the engine is thoroughly warmed up. My limited engineering brain agrees with this. But, I began thinking about what I have read in various publications, and began wondering.

The Service Bulletins state the engine should be hot. The book titled "The Model A Engine" by William H. & Paul H. McRee states hot also. So, I began to wonder how the "cold" re-torqueing method came about, and I discovered one such item (there are probably others).

The "modern silicon gasket" instructions state the engine must be cold before re-torqueing. In fact, it is recommended the engine set over-night before re-torqueing.

I am not trying to cause a big discussion on "hot vs. cold", but why is this statement being made, and are there other manufacturers or publications that state re-torqueing cold also?

Sorry, I just have a curious mind.