How can two engines have similar power & torque but hugely different fuel consumption? Are bigger (capacity) engines intrinsically thirstier? Details next.  Save thousands on any new car (Australia-only): https://autoexpert.com.au/contactAutoExpert discount roadside assistance package: https://247roadservices.com.au/autoexpert/Did you like this report? You can help support the channel, securely via PayPal: https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=DSL9A3MWEMNBW&source=urlHere’s a question from a dude named Dave, concerning the King (of mediocrity) - Toyota.   "I'm comparing a Landcruiser Troopie with a new Prado. The Troopie has a V8 with 151kW & 430Nm. The Prado has an inline four-cylinder with 150kW & 500Nm. (Approximately the same power/torque.) But the Troopy uses about 15L/100 compared to the Prado at 10L/100 (both ballpark real world figures, not the ADR fantasies).   "If they output about the same power, where is the big difference in fuel economy coming from?  The weight of each car?  Aerodynamics?  Gearing?  Feeding four extra cylinders, with extra engine internal friction?  "If they were the same weight, and had the same Cd value, would they accelerate/overtake the same and have the same fuel usage, even though one is V8 and one an I4?" - David Deere  The data:  Diesel = 45 kJ/g (and if you do that once a second = 45kW) So, 2.2g/sec = 100kW (of potential heat energy) Combustion efficiency = 40% = 40kW @ crankshaft 15% loss via transmission = 34kW @ wheels  Prado: 2.755cc 6sp (5th = 0.** Hyundai/Kia 2.2 @ 147 kW & 440 Nm I4 ** Mazda 2.2 @ 140 kW & 450 Nm I4  Plus: Troopy needs to drive twice as many valves to do the same job, pumping more oil and water, etc. (Not as volumetrically efficient, and higher pumping losses, etc.)  And the single turbo 4.5 V8 is a rubbish engine - like it’s the cheap, slutty version of the 4.5 TT, which makes 32.5% more peak power, 51% more peak torque and returns slightly better fuel economy - despite being in a platform weighing 500kg more.