The sprint engine was designed in the days of slide rules when longiviity & simplicity were a selling feature.
Thus it is so over engineered it is not funny and allows then to have a service life well over 50 years.
Now we have computers and can design an engine to a fixed number of running hours using 1/2 the weight of materials for 2 times the power output.
Some say it is an advancement, but Henry Ford proved conclusively that you mak more money selling a flimsey piece of kit that will only just hold together for long enough to outlive warranttee to everyone than flogging fewer higher priced higher profit units that will run forever.
The advent of computers, desktop designs ans simulated prototyping has taken Fords theory to whole new level.