I am bringing this over from the steam tech list can anybody give me any help here " I seem to recall reading once that some Denver and RGW
steam locos were equipped with a means of varying the
valve lead.(independently of the cut-off?) The article, which
I can't track down, didn't go into details as to how it
was done. Does anyone know more about this, or is it a
figment of my imagination ?
Presumably, the idea was to improve starting characteristics
without compromising the power output at running speeds." Any help appreciated TIA Wooly