Why do larger engines get less MPG? Couldn’t a V8 be geared to a lower RPM and consume the same or less than an I4 at a given speed?

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I imagine some of the difference is due to weight (larger engines being in trucks) or performance (sports cars made to accelerate rather than cruise well), but it seems that almost without fail the bigger the engine the less MPG, I don’t understand where the extra energy goes if not to the wheels

In: Engineering

19 Answers

Anonymous 0 Comments

> I don’t understand where the extra energy goes if not to the wheels

It’s lost through friction and heat

It is possible to engineer engines to be more efficient at all kinds of configurations, but it’s a numbers game

It’s not worth making an engine that gets 2 mpg more if it is ten times the price of the 2 mpg worse engine, which is kind of what F1 does with its 1.6L V6 engines

They have and had complex systems to recover energy from the engine that normally would be lost, but they are and were so complicated and costly to produce that teams want to get rid of some parts. You can read up on the MGU-K and MGU-H for more information on those, but I digress

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