Some of the many engines in the Glen Curtiss Museum.
5 years ago I modified a Briggs lawnmower engine to operate on the same modified 4 stroke cycle as the Mono. It keeps the exhaust valve open a very long time, and sucks air back into the cylinder thru the open exhaust valve, pulling in the very rich gasoline mixture thru inlet ports at the bottom of the cylinder, which then dilutes with the air already in the cylinder. The Seguin brothers sure used their imagination to figure these engines out!!!
![](https://s2.save4k.ru/pic/qCKrlJGcIfk/mqdefault.jpg)