The Wartsila-Sulzer RTA96-C turbocharged 14-cylinder model is the most powerful diesel engine in the world. It’s designed to accommodate as large a vessel as might be commercially viable, which in turn can still stick to a single-engine, single-propeller design. It’s 89 feet long, 44 feet tall, and weighs 2300 tons. Each cylinder produces 7780 horsepower. Each cylinder. Total displacement, nine hundred cubic feet.
That goes for the largest model. Pictured at left is the bedplate for the eight-cylinder version.
Interestingly, in addition to being the most powerful, it’s also the most efficient. Among the features you won’t find in most smaller engines, is a crosshead design used to take the sideways force away from the pistons, which reduces the wear-and-tear to the cylinder block over time. I suppose it would have to lower the accumulation of operational heat as well.