As most of you know, the postwar locomotives with smoke units run ~16ohm element. The liquid conversion runs a 27ohm resistor. This is most likely just a compromise and best generic choice to offer. Assuming we are running liquid conversions in these locomotives, the problem is that postwar locos run at different speeds at a given voltage. 12v will make a 675 move pretty good while a 726 or 773 will move slower. The smoke heater is seeing 12v in both instances resulting in anemic smoke production. You can compensate for this by installing different value resistors for different locomotives. It works, but you still have a fine line in between making good smoke and that awful burning smell.
I did some experiments regarding heat produced for 22,25 and 33 ohm resistors.
@12v
22 Ohm=233F
25 Ohm=223F
33Ohm=204F
@18v
22 Ohm=460F
25 Ohm=311F
33 Ohm=289F
Is it possible to install a simple voltage regulator to limit a 22ohm resistor to say 13v? That would limit the temp to about 240F, get smoke going sooner at low speeds and eliminate burning the fluid.
