Welcome to ModelEngineMaker !If you have problems registering or logging in, please use the contact menu option to request assistance.
Carburetor, A Stromberg in Miniature, by Lee Root/Washburn: 31-3; 32-3; 33-3
I agree that 6mm is on the large size for this engine however that is the smallest I think I will be able to make. As it has a variable venturi the problem is not so great, the piston will just not rise all the way.