Cubic inch

Cubic inch
Cubic inch
	An engine with a swept pistondisplacementof 502 cubic inches
General information
Unit system	Nonstandard
Unit of	volume
Symbol	in3, cu in
Conversions
1 in3in...	... is equal to...
SI derived units	16.387064mL
US customary	1⁄231US Gallon
nonstandard	1⁄1728ft3

Thecubic inch(symbolin³) is aunit of volumein theImperial unitsandUnited States customary unitssystems. It is the volume of acubewith each of its three dimensions (length, width, and height) being oneinchlong which is equivalent to1⁄231of a US gallon.^[1]

The cubic inch and thecubic footare used as units of volume in theUnited States,although the commonSIunits of volume, theliter,milliliter,andcubic meter,are also used, especially inmanufacturingandhigh technology.One cubic inch is exactly16.387064mL.

One cubic foot is equal to exactly 1,728 cubic inches (28.316846592 L), as 12³= 1728.

Notation conventions

The following abbreviations have been used to denote the cubic inch: cubic in, cu inch, cu in, cui, cu. in.
TheIEEEstandard symbol is: in³^[1]
Ininternal combustion engines,the following abbreviations are used to denote cubic inchdisplacement:c.i.d., cid, CID, c.i., ci

Equivalence with other units of volume

One cubic inch (assuming an international inch) is equal to:

0.000578704 cubic feet (1 cu ft equals 1,728 cu in)
Roughly 1tablespoon(1.0 U.S. gallon = 256 U.S. tablespoons = 231 cubic inches)
About 0.576744 imperial fluid ounces
About 0.554113 US fluid ounces
About 0.06926407 American/Englishcups
About 0.000450581imperial bushels
About 0.000465025 US bushels
About 0.00360465 imperial gallons
About 0.00432900 US gallons (1.0 gallon equals 231 cu in exactly [3 in × 7 in × 11 in])
About 0.0001030715 barrels of crude oil (1.0 barrel equals 42 gallons, by definition, or 9,702 cu in)
Exactly 0.016387064 liters (1.0 liter is about 61.0237 cubic inches)
Exactly 16.387064 milliliters orcubic centimeters(which in turn is approximately 0.0610237 cubic inches)
Exactly 1.6387064×10⁻⁵cubic meters (1.0 m³is about 61,023.7 cubic inches)

Uses of the cubic inch

Electrical box volume

The cubic inch was established decades ago in theNational Electrical Codeas the conventional unit in North America for measuring the volume of electrical boxes. Because of the extensive export of electrical equipment to other countries, some usage of the non-SI unit can be found outside North America.

Engine displacement

North America

The cubic inch was formerly used by theautomotive industryandaircraft industryin North America (through the early 1980s) to express the nominal engine displacement for the engines of newautomobiles,trucks,aircraft,etc. The cubic inch is still used for this purpose in classic car collecting. The auto industry now useslitersfor this purpose, while reciprocating engines used in commercial aircraft often have model numbers based on the cubic inch displacement. The fifth generationFord Mustanghas a Boss 302 version that reflects this heritage - with a five-liter (302 cubic inch) engine similar to the original Boss.Chevrolethas also revived this usage on its 427Corvette.Dodgehas a "Challenger 392" (a conversion from its 6.4 liter V8 engine).

References

^^a ^bIEEE Standard Letter Symbols for Units of Measurement (SI Customary Inch-Pound Units, and Certain Other Units)(Technical report). IEEE. 2004. 260.1-2004.

[IEEE_260.1-2004-1] IEEE Standard Letter Symbols for Units of Measurement (SI Customary Inch-Pound Units, and Certain Other Units)(Technical report). IEEE. 2004. 260.1-2004.

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