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A comment on “Super Engine” may fundamentally change the way internal combustion engines work. Parent comment

Re:“Super Engine” may fundamentally change the way internal ... by dredmorbius on Thursday February 25, 2016 @03:59PM (#11177738)
Compression required to "diesel" petrol (gasoline) is lower, which is why some autos have the problem of continuing to run ("diesel") after the ignition (and spark) are shut off. Most now incorporate other controls and limiters, such as controlled fuel injection, to eliminate this.

Gasoline is comprised of a shorter set of hydrocarbons (mostly 6, 8, and 10 chain) than diesel (about 12-16 chain length, though 8-21 carbon are listed at Wikipedia). Volatility (and ignitability) increase with shorter chains -- methane (C2H6) and butane (C4H10) -- that is, two and four chain hydrocarbons -- are both gaseous at or near room temperature.

Longer chains still get you heavy fuel oils, tars, etc.

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Re:“Super Engine” may fundamentally change the way internal ... by userbinator on Friday February 26, 2016 @12:29AM (#11179946)
Longer chains still get you heavy fuel oils, tars, etc.

...and eventually that results in simple plastics like polyethylene, which is basically a very long chain hydrocarbon:

https://en.wikipedia.org/wiki/Polyethylene

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Re:“Super Engine” may fundamentally change the way internal ... by dredmorbius on Friday February 26, 2016 @12:54AM (#11180015)
Yep. I regret not having studied more chemistry in college. It's only started coming into context for me recently.
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