Engine design in old tractors prioritized high torque at low operating engine revolutions per minute (RPM). Heavy flywheels stored kinetic energy, preventing engine stalls when plows struck tough tree roots, heavy clay, or buried rocks. This low-speed pulling capability allowed small-horsepower engines to accomplish surprisingly demanding earth-moving and tillage tasks across stubborn... https://www.aniarticles.com/79175-old-tractor-before-buying-best-deals-buying-guide