I saw Big Boy today in West Chicago. It is big. The town was buzzing. I asked an engineer what fuel they now burn to make steam. "Used motor oil". Phil
My wife went there this morning to see it leave. She was really impressed with it moving on its own power and she could care less about my car collection. If it got her attention it must have been a sight to see.
Found a few videos of it under power It looks to me like the helper engine is doing all the work. At least at start up it does.
It is really cool to see live steam under way. But my favorite engine will neve see the tracks again unless I come up with several million to restore it. That and the cal. Railroad Museum let it get put back into service. The 'Cab Forward' (sorry no pics) but imagine a inter city trolley car on so many steroids it has ability to do what the Big Boy can do. Mike