# What determines how powerful an engine is?
**URL:** https://discourse.cataclysmdda.org/t/what-determines-how-powerful-an-engine-is/14158
**Category:** The Garage
**Created:** [August 21, 2017, 9:45pm UTC](https://discourse.cataclysmdda.org/t/what-determines-how-powerful-an-engine-is/14158 "2017-08-21T21:45:53Z")
**Posts on this page:** 5
**Page:** 1
### Author:  [@DeWolf](https://discourse.cataclysmdda.org/u/DeWolf)
#### Post date: [August 21, 2017, 9:45pm UTC](https://discourse.cataclysmdda.org/t/what-determines-how-powerful-an-engine-is/14158/1 "2017-08-21T21:45:53Z")
Electric motors have a power stat and an epower stat, which I presume mean how powerful said motor is and how much electricity it uses respectively. However as far as I have seen in the jsons combustion engines only have an epower stat so I am wondering what determines how powerful an engine is? Also for the engine items I have seen a stat called displacement can someone tell me what that is if you can?
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### Author:  [@Vollinger](https://discourse.cataclysmdda.org/u/Vollinger)
#### Post date: [September 1, 2017, 10:09am UTC](https://discourse.cataclysmdda.org/t/what-determines-how-powerful-an-engine-is/14158/2 "2017-09-01T10:09:18Z")
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seems like ‘displacement’ is pretty much ‘power’ stat for combustion engines, with some penalties for damage or engine faults
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### Author:  [@DeWolf](https://discourse.cataclysmdda.org/u/DeWolf)
#### Post date: [September 1, 2017, 4:41pm UTC](https://discourse.cataclysmdda.org/t/what-determines-how-powerful-an-engine-is/14158/3 "2017-09-01T16:41:12Z")
[quote=“Vollinger, post:2, topic:14158”][https://github.com/CleverRaven/Cataclysm-DDA/blob/44310f6bba6e3b60eb3ecbd58859a72e1219ec52/src/vehicle.cpp#L1357](https://github.com/CleverRaven/Cataclysm-DDA/blob/44310f6bba6e3b60eb3ecbd58859a72e1219ec52/src/vehicle.cpp#L1357)
seems like ‘displacement’ is pretty much ‘power’ stat for combustion engines, with some penalties for damage or engine faults[/quote]
Welp I should have been doing this by now but I guess it’s time for a bit of experimenting.
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### Author:  [@Coolthulhu](https://discourse.cataclysmdda.org/u/Coolthulhu)
#### Post date: [September 2, 2017, 7:02am UTC](https://discourse.cataclysmdda.org/t/what-determines-how-powerful-an-engine-is/14158/4 "2017-09-02T07:02:26Z")
It’s just the displacement.
It determines power, fuel usage, minimum fuel usage (huge engines waste more fuel when idle) and noise.
Power of an engine is equal to its displacement. Fuel usage scales linearly with load on the engine (ie. two engines doing same work will use same amount of fuel energy).
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### Author:  [@DeWolf](https://discourse.cataclysmdda.org/u/DeWolf)
#### Post date: [September 2, 2017, 7:28am UTC](https://discourse.cataclysmdda.org/t/what-determines-how-powerful-an-engine-is/14158/5 "2017-09-02T07:28:24Z")
[quote=“Coolthulhu, post:4, topic:14158”]It’s just the displacement.
It determines power, fuel usage, minimum fuel usage (huge engines waste more fuel when idle) and noise.
Power of an engine is equal to its displacement. Fuel usage scales linearly with load on the engine (ie. two engines doing same work will use same amount of fuel energy).[/quote]
Thank you for the more indef explanaition.