Thanks for the email. Jim's GS4 is only one of two alcohol fired GS4's that are highly modified by Gordon Watson. Jim indicated that the GS4 ran for an hour with a consistent performance. The engine is not only impressive based on the number but the attention given to it by those future train spotters that were pacing the engine.
Hope there is more coverage to come!
Thanks for the wonderful videos. I love the look on the kid's faces as they chase the GS4. I also like the interesting dog bone layout with the gentle curves and good views for spectators. Keep the videos coming.