Actually, I need to eat a little crow - amazing how the memory fails when one is trying to remember facts.
It turns out that UP's "Big Blow" turbines were fairly successful at what they did do - which was haul big freight loads at high speeds on the relatively flat desert rail sections. At the time (1952, it turns out, until the last of 'em were retired by 1970), "Bunker C" was pretty much waste, since the technology hadn't been invented yet to crack heavier oils down to more useful stuff like plastic feedstock, diesel, gasoline, etc. Given that, they designed a gas turbine that could burn the stuff and do some very good cost/mile numbers. Since it was a very heavy, tar-like goop, they had to heat it to make it liquid enough to flow through pumps and fuel lines to get to the turbine!
UP had done some analysis, and realized that the maintenance costs (around $7,000 per year) were pretty much fixed, regardless of the horsepower of the actual unit. Given that, they decided it was more economical to build bigger, high-horsepower units that could pull trains by themselves rather than needing consists of several units. The original gas turbine electric locomotives (GTEL) had a 4,500 hp prime mover. The later "Big Blow" units had a 8,500 hp turbine and were so loud they were banned from hauling stuff into Los Angeles.
Eventually, the supply of cheap Bunker C dried up as cracking technology came into use, and they were retired and sold for scrap.
The one that I was thinking of was another prototype that burned pulverized coal. It was a monster, with a converted 2,000 hp PA1 as the cab unit, a 5,000 hp turbine unit, and a processing unit converted from a steam locomotive tender that pulverized nugget coal into a flour-like consistancy that could be pumped into the burners of the turbine. Problems with erosion of the turbine blades due to fly ash from the burning coal made it impratical, not to mention the limited application of the turbine in the first place. It was a real frakenstein thing, quite a lash-up!