Have to say most of the trains that passed me by had the EMD "whine" sound of high horsepower.
The GE's have no "whine" sounds. Boiled down...EMD's sound like jets and GE's sound like helicopters.
Uke said
12:56 PM, 11/17/17
Simplest explanation: EMD's 'high-horsepower' units from the earliest 567-D, up to the latest 710-G3 two-stroke engines ALL have gear driven turbochargers. When the throttle is advanced beyond 6 notch, exhaust gases exiting will begin driving the turbo, and a 'clutch' on the gear train of the turbo will release the turbo... Then exiting exhaust gases will alone drive it.
The EMD H series engines (four-stroke design) will begin their turbo whine at about 4-5 notch as exiting exhaust gases drive the turbo alone.
Both engine designs have been improved progressively, through fuel injection control, over-turbocharging, air filtration, and after-treating exhaust gases. The best perfotming most fuel efficient diesels have been produced by GE however. They employ a 'start-stop' control that shuts down idling engines when not needed. Restart is tied to air-pressure (train air, etc,), ambient air temperatures. and battery charge.
EMD accomplishes similar via ultra-low idle speeds, where fuel injection control barely allows the engine to run. However both EMD and GE engines produce more than adequate horsepower/electrical/tractive-effort to do the job!
...weather. Non-stop precip. In liquid form.
https://www.youtube.com/watch?v=5Thz5Gap7cc
The GE's have no "whine" sounds. Boiled down...EMD's sound like jets and GE's sound like helicopters.
Simplest explanation: EMD's 'high-horsepower' units from the earliest 567-D, up to the latest 710-G3 two-stroke engines ALL have gear driven turbochargers. When the throttle is advanced beyond 6 notch, exhaust gases exiting will begin driving the turbo, and a 'clutch' on the gear train of the turbo will release the turbo... Then exiting exhaust gases will alone drive it.
The EMD H series engines (four-stroke design) will begin their turbo whine at about 4-5 notch as exiting exhaust gases drive the turbo alone.
Both engine designs have been improved progressively, through fuel injection control, over-turbocharging, air filtration, and after-treating exhaust gases. The best perfotming most fuel efficient diesels have been produced by GE however. They employ a 'start-stop' control that shuts down idling engines when not needed. Restart is tied to air-pressure (train air, etc,), ambient air temperatures. and battery charge.
EMD accomplishes similar via ultra-low idle speeds, where fuel injection control barely allows the engine to run. However both EMD and GE engines produce more than adequate horsepower/electrical/tractive-effort to do the job!