Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

Benny, your engine looks terrific.

Regarding an exhaust cap, if you are referring to those flapper lids on top of the stack, I recommend you dont do it. A hit & miss engine does not want a long exhaust pipe. The longer the pipe, the more it loses the ability to cool itself while free wheeling. A flapper cap will further exacerbate an already less than desirable arrangement by not letting cool air to travel back into the cylinder 20 to 30 times between firing. That's my 2 cents worth!

Again, it looks fantastic!

Gil