Inline Engine Types and Components :- The inline engine are also named as straight engine which is an internal combustion engine with all the cylinders aligned in a single row having no offset.
These engines are commonly found in four, six and eight cylinder configurations which have been used in popularly in automobiles, locomotives and aircraft whereas the term in-line has a wider meaning when it is applied to the engine of the aircraft.
A straight or inline engine is considerably quite easier to construct as compared to any other equivalent horizontally opposed or V engine as both of the cylinder bank and the crankshaft can be milled from a single metal casting which is required for fewer cylinder heads and camshafts.
In-line engines are usually smaller than the overall physical dimensions and designs like the radial can be mounted in various directions. Straight configurations are quite simpler as compared to the V-shaped counterparts.
As by now it is known that the straight engines are also called inline engines which have all cylinders that are aligned in one row along with the crankshaft with no offset. When a straight engine is mounted at a particular angle it is referred to as a slant engine.
Types of inline engines
• straight-2 or Parallel Twin
• straight-3 or Inline Triple
The inline-four engines are the most popular four-cylinder configuration, although the straight-6 has largely given way to the V6 engine, which does not naturally run in the smaller or both length and height which is easier to fit into the bay of the engine of a comparatively smaller as well as modern cars.
There are some manufacturers like Acura, Audi, Ford, Mercedes-Benz, Volkswagen and Volvo who have been consistently using the straight-five configurations whereas the General Motors Atlas family includes a straight-four, straight-five and even straight-six engines wherein some small cars are found having inline three engines.
The straight-eight engine was one of the prestige engine arrangement which could be made cheaply as compared to a V-engine by the makers of the luxury car who would deeply focus on other specifications and also the geometric ones which calls out engines that are more powerful than any V8 engine.
Design of straight-four engine
A four-stroke straight-four engine is always found having a cylinder on its power stroke, unlike other engines there are fewer cylinders which had no power stroke which occurred at the certain times.
As compared to the V4 engine or a flat-four engine, a straight-four engine has only one cylinder head, which is found reducing the complexity of the engine and also its production cost.
Whenever a straight-four engine is installed at an inclined angle, it is referred to as slant-four engine
Source : Engineering Learner