A 4-53 would be a Detroit Diesel, a 2-cycle engine with a blower. (not a turbo). They're at least 250 pounds heavier than a stovebolt 6 and they have a very limited RPM range. (1,750 to 2,150) You'd need at least 6 speeds in the transmission, and 8 would be better. They're a great engine for a big boat, or an industrial application like a generator or water pump, but I don't think I'd want one in a truck. The 4-53 designation means 4 cylinders, 53 cubic inches per cylinder, so the displacement would be 212 cubic inches. Other Detroit engines had 71, or 92 cubes per cylinder, and were used in big trucks, cranes, construction equipment, Greyhound buses, etc.
The blower used on a lot of drag race engines was a 6-71, right off a Detroit Diesel! "Screamin' Jimmy" engines got their name from the fact they fired on every downstroke of the piston, and had those noisy Rootes-type blowers. They lose torque if they're lugged down, but as long as they're run wide open, right up against the governor, they do a lot of work.
Jerry
