LOL...thanks George, I'd forgotten I put that on a web page for future reference

Bill..agreed that a lot of engines used ports in the piston (all the old OS Max's had them) but in the Doolings (and Madewell as Jim pointed out) it was the only transfer method. I remember seeing photos of the Carter Dooling where one of their hop up mods was to file the round ports into rectangular slots in the piston and liner. It seems to me that if ALL the mixture has to pass through the piston skirt then it should help keep both the piston crown and the wrist pin area much cooler.

But whichever way it was assembled, in my eyes the Dooling 29 was and still is the best looking model engine ever made, even better than its big brother.