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Straight-six engine
A straight-six engine (also referred to as an inline-six engine; abbreviated I6 or L6) is a piston engine with six cylinders arranged in a straight line along the crankshaft. A straight-six engine has perfect primary and secondary engine balance, resulting in fewer vibrations than other designs of six or fewer cylinders.
Until the mid-20th century, the straight-six layout was the most common design for engines with six cylinders. However, V6 engines gradually became more common in the 1970s and by the 2000s, V6 engines had replaced straight-six engines in most light automotive applications.
Due to their high and smooth torque, simplicity and reliability, weight and space, and balanced power delivery, straight-six engines are a common power source for trucks and buses.
In terms of packaging, straight-six engines are almost always narrower than a V6 engine or V8 engine, but longer than straight-four engines, V6s, and most V8s. Compared to V-configuration engines with similar power and displacement, the straight configuration has fewer injectors, a single head, and a single exhaust manifold, all contributing to better reliability and performance.
Straight-six engines are typically produced in displacements ranging from 2 to 4 L (122 to 244 cu in), however engines range in size from the 0.7 L (43 cu in) Benelli 750 Sei motorcycle engine to the 10,972.2 L (669,565 cu in) Wärtsilä-Sulzer RTA96-C two-stroke marine diesel engine. Due to its well-balanced configuration, the straight-six can be scaled up to substantial sizes for heavy trucks, locomotives, industrial and marine use.. When two straight-six engines are mated with a common crankshaft it forms a V12 engine.
If an appropriate firing order is used, a straight-six engine has perfect primary and secondary engine balance. The primary balance is due to the front and rear trio of cylinders moving in pairs (albeit 360° out of phase), thus canceling out the rocking motion present in a straight-three engine. The secondary balance is due to the crank throws being arranged in three planes offset at 120°, resulting in the non-sinusoidal forces summing to zero for all free forces until the sixth order.
The engine balance characteristics of a straight-six engine compare favorably with the more common straight-four engines, V6 engines, and V8 engines which experience significant secondary dynamic imbalance, resulting in engine vibration. As engine reciprocating forces increase with the cube of piston bore, the straight-six is a preferred configuration for large truck and industrial engines.
An even-firing six-cylinder two-stroke engine requires ignitions at 60° intervals, or else it would run with simultaneous ignitions and be no smoother than a triple in power delivery. As such, it also requires crank throws at 60° – . Such designs appear to have been limited to diesel engines such as the Detroit 71 series, marine engines, and outboard motors.
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Straight-six engine AI simulator
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Straight-six engine
A straight-six engine (also referred to as an inline-six engine; abbreviated I6 or L6) is a piston engine with six cylinders arranged in a straight line along the crankshaft. A straight-six engine has perfect primary and secondary engine balance, resulting in fewer vibrations than other designs of six or fewer cylinders.
Until the mid-20th century, the straight-six layout was the most common design for engines with six cylinders. However, V6 engines gradually became more common in the 1970s and by the 2000s, V6 engines had replaced straight-six engines in most light automotive applications.
Due to their high and smooth torque, simplicity and reliability, weight and space, and balanced power delivery, straight-six engines are a common power source for trucks and buses.
In terms of packaging, straight-six engines are almost always narrower than a V6 engine or V8 engine, but longer than straight-four engines, V6s, and most V8s. Compared to V-configuration engines with similar power and displacement, the straight configuration has fewer injectors, a single head, and a single exhaust manifold, all contributing to better reliability and performance.
Straight-six engines are typically produced in displacements ranging from 2 to 4 L (122 to 244 cu in), however engines range in size from the 0.7 L (43 cu in) Benelli 750 Sei motorcycle engine to the 10,972.2 L (669,565 cu in) Wärtsilä-Sulzer RTA96-C two-stroke marine diesel engine. Due to its well-balanced configuration, the straight-six can be scaled up to substantial sizes for heavy trucks, locomotives, industrial and marine use.. When two straight-six engines are mated with a common crankshaft it forms a V12 engine.
If an appropriate firing order is used, a straight-six engine has perfect primary and secondary engine balance. The primary balance is due to the front and rear trio of cylinders moving in pairs (albeit 360° out of phase), thus canceling out the rocking motion present in a straight-three engine. The secondary balance is due to the crank throws being arranged in three planes offset at 120°, resulting in the non-sinusoidal forces summing to zero for all free forces until the sixth order.
The engine balance characteristics of a straight-six engine compare favorably with the more common straight-four engines, V6 engines, and V8 engines which experience significant secondary dynamic imbalance, resulting in engine vibration. As engine reciprocating forces increase with the cube of piston bore, the straight-six is a preferred configuration for large truck and industrial engines.
An even-firing six-cylinder two-stroke engine requires ignitions at 60° intervals, or else it would run with simultaneous ignitions and be no smoother than a triple in power delivery. As such, it also requires crank throws at 60° – . Such designs appear to have been limited to diesel engines such as the Detroit 71 series, marine engines, and outboard motors.