Question

In which of the following condition the engine is known as over-square engine?

(a) d < L

(b) d > L

(c) d=0

(d) L=0

This question was posed to me during a job interview.

Origin of the question is I.C. Engine Components topic in section Internal Combustion Engine of Farm Machinery

Answer 1

Right choice is (b) d > L

To explain I would say: L/d, known as stroke to bore ratio, is an important parameter in classifying the size of the engine. If d < L, it is called under-square engine. If d = L, it is called square engine. If d>L, it is called over-square engine.