Heh. Largest single diesel prime mover I’m aware of is General Motors’ Electro-Motive 645 V20, which appeared in only a few locomotives (the SD45, SDP45, F45 and FP45 series) but had crankshaft problems. (The “645” stands for 645 cubic inch displacement per cylinder, so the 20-645E3/B would have a total displacement of 12,900 CID; bore is 9 inches and stroke is 10 inches.)
Was just kidding around. Those locomotives are huge so I just guessed at a number; not being very technical.
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Those things are still moving most of our freight.
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