Comments by "Seegal Galguntijak" (@Seegalgalguntijak) on "Engineering Explained" channel.

  1. When sitting in drive at a stop light and the engine rpms are lower, the engine also gets a richer air-fuel-mixture for it not to stall. So the difference in fuel economy should only be the amount that the torque converter heats up over time by being spun at the one end but being blocked to spin at the other.
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  2. There's one good reason to put it out of drive into neutral on a stop light and that is to not having to press on the brake pedal all the time. But that's just me. And of course, driving a manual, I can't really compare (but I still like to do, because at some point in time, I might be driving an automatic, and I want to know what I'll be getting myself into!)
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  3. Whenever I drive an automatic (or something similar like a DSG style double-clutch transmission), I feel uncomfortable having to "hold" the car with the brakes at a stop light, so I instinctively put it in neutral. In fact, that's what you'd do with a standard as well (I have driven mostly standard transmissions in my whole life, because they are more common over here in Europe).
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  4. Why is the spark plug igniting the mixture while the piston is still compressing, wouldn't it be better to ignite right at TDC for each piston?
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  5. In my youth, I even turned off the engine while going down a hill! I put the manual gearbox in neutral and then turned the key so the ignition would shut down, then I turned it back for the steering wheel not to lock (being very conscious that my brake booster would run out of boost after the first time of applying the brakes). That way, I even reached up to 190km/h on the speedometer, which was never possible with the engine on (it always reached 175-180 and never went any further). I must admit, these were some particularly steep hills, and I wouldn't do that today (especially since nowadays, cars don't have carburetors any more), but it is what I did and this one 8% downslope over 2km or so gave me a higher speed than what was ever possible under the car's own enine power ;)
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  6. Wow, that's pretty typical for an American paint job. Don't care about the details, and stuff like that. This is why the Tesla, albeit being a really good car, unfortunately has no chance on the German market. Which sucks, because I'd like to buy a used one. But that's like buying a new car and getting a used one.
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  7. For how long has the gas in the USA been E10?
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  8. Mazda seems to be the only innovative manufacturer that actually continues to develop the internal combustion engine in order to make it better. European and other Asian manufacturers sit on what they have, and American manufacturers are slowly catching up to all the others. Mazda is at the leading edge, and if they were to combine this engine with Toyota's HSD drivetrain, we would finally have the best of both worlds for as long as we still need internal combustion of fuel.
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  9. I guess methanol burns hotter. However, I still only use E5 fuel with only 5% of ethanol (living in Germany, using European steady quality gasoline). Although this is a bit more expensive, ethanol contains fewer chemical energy per volume, so the fuel efficiency of the engine would be slightly worse. This compensates the slightly higher price per liter of the E5 fuel. Or at least it does on paper, but since I have neither tried E10 fuel, nor do I keep exact track of how much fuel my car uses per 100km (and it's old enough to not be able to calculate this on its own), I can't actually prove it. But I can say that I feel better with the E5 fuel.
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