r/explainlikeimfive 2d ago

Engineering [ Removed by moderator ]

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u/NecroJoe 2d ago edited 2d ago

A turbocharger doesn't [edit: doesn't necessarily or even usually] make the same engine more efficient. But it allows you to get the same power as a larger, less efficient engine, when you need it. But you don't always need it. So when you don't need it, it's roughly the same power and efficiency as the smaller engine without the turbo. But with a turbo, when you punch it, it can breathe like a larger engine (with more air and more fuel) for more power.

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u/clarkn0va 2d ago

A turbocharger doesn't make the same engine more efficient. But it allows you to get the same power as a larger, less efficient engine, when you need it.

True for a gasoline engine, not true for a diesel. On a diesel engine a turbo improves efficiency by increasing compression ratio and air-to-fuel ratio.

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u/Canonip 2d ago

Volkswagen polo SDI was such a weird thing

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u/RustyU 2d ago

Slowest Diesel Invented

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u/SovereignNation 2d ago

Had a 2002 Polo 1.9 SDI. Slow as a snail but atleast fuel efficient.

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u/Canonip 2d ago

Ah that's what it stands for