Comments by "geemy" (@geemy9675) on "WHY are HORSEPOWER and TORQUE CURVED?" video.

  1. that's why free valve is the pinnacle of combustion engine design (for road cars. not talking about drag racing, F1). almost perfectly flat torque curve from 1500 to 7500rpm. 300hp/l , 43.5 psi bmep. no throttle bodies/pumping loss, independent valve lift/timimg/duration controls how much air goes in, how many valves are used, and how hard the turbo is spooled up, acting both as anti lag, waste gate, you can theoretically do cylinder deactivation(not very likely to happen on a 3cyl though?) , skip revolutions at low loads, you can also do air brakes like on semis. you can do different cycles to like Atkinson, or heck you could even run a 2 strokes cycle, although probably not very efficiently, considering its not designed for scavenging like a 2 stroke cylinder with ports, and has no expansion pipe. also who would do that to a 2M car 🤣🤣
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  2. the torque curve on electric motors doesn't start dropping suddenly because of back emf, because back emf is proportional to the rpm. power is limited for a variety of reasons. battery power output is limited, controller power output is limited too, and finally the motor is also rated for maximum power. sending more power will generate more heat and eventually overheat or even melt the motor. whichever of these limits is reached the first, caps the motor power. then back emf is the reason why dyno chart of electric motors will not have perfectly flat horsepower plateau. even if controller keeps sending the same amount of electrical power, back emf will reduce the mechanical power produced, with more and more losses as rpm rise. tesla plaid seems to be almost an exception with very little power drop. maybe they just artificially limited the power at midrange rpms to allow this almost flat power curve? BTW motors can have different nominal and peak power. you may have automatic fallback to lower power - limp mode- when its overheating, like on most EVS. on cheaper powertrains though, like ebikes, especially DIY ebikes, its often up to the rider to avoid putting out peak power or amps for too long, and you can damage or even destroy the motor on long climbs, or with too much payload with combinations of climbs/cargo/passenger
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