Hi I have started my winter project a 1889 Welch & Lawson engine full scale or larger. I am just working from a picture and patent drawings and don't know the real size. I have a nice curved spoked flywheel that needs an engine so I will use it and build the engine to fit it. The fly wheel is 30 inch dia. ;D This engine has flame ignition and a spool intake and carry flame valve. The shape of the engine and the flame ignition will be a good challenge and a lot of fun. Tom