I replaced all the incandescent lights in the Budd cars with strips of LEDs. An AM Pacific pulling 6 Budd cars at 10 volts, which is very fast, draws 0.5 amperes of direct current. The headlight in the Pacific is still an incandescent bulb. An American Models E8 pulling the same cars at the same 10 volts draws the same amount of current but runs very slightly slower--still faster than any of the plastic figures in the cars finds comfortable. An ABBA consist of SHS F7s, all powered, draws 2 amps pulling the same cars. Their speed is much slower under Locomatic control at 10 or even 12 volts, but that speed is still a bit faster than realistic on my layout.
The LEDs in the passenger cars reduce the required current--and heat--significantly. Buck-boost modules keep the lighting uniform and steady no matter what speed the trains run, as long as the applied voltage is above 3.5 volts or so. The conversion to LEDs was worth the effort.
