Imbert cone height

I’m planning to build a V Hearth Imbert to install on a 14hp lawnmower, and I plan to use the hearth dimension chart found in the library, using the A row, or the first line. While I understand the process behind the gasifier, and I understand the drawing, I just cannot find the height dimension of the cone. (red)

While at first I thought you simply subtract “h” from “H” to find the difference, I noticed that these dimensions do not have endpoints that line up at the top, so finding the difference would not give an accurate value. This dimension seems like it would be important enough to be on the chart, so I wonder am I just reading the chart wrong. If not, what is the calculation to find the height of the cone?

The distance from “h” to “H” will add up in scale to the engine. Since it’s a cone shape it will gain volume as H gets longer.

I can’t remember exactly but there is a specific volume you want to meet per your CFM.

Edit: Let me check the table again to see if I can clarify more coherently, I could be entirely wrong with that I wrote above.

Here you can find something maybe.


I’m not sure but I think those dimensions are in Ben Peterson’s book.