Trick wrote:That’s an question for the Neo-MMA guys. We traditionals are more horse and wagon types
everything wrote:Can anyone explain it “for dummies”?
Since MA people like to claim physics understanding, maybe someone here can.
The car guys all fail.
If you can get me to understand it, I’ll pay attention to your physics claims. If not, “biomechanics” stays in the same category as woo woo for me as far as the blah blah blah (not anyone’s fault).
Snork wrote:I'll have a go since I'm here.
Horsepower is (basically) torque times rotational speed. So if you apply a torque (rotational force) to something and it gets some speed you can say you have power. In the case of car engines, you usually hear about it in the opposite direction, a given engine has some horsepower (it's been designed and built and its stats have been measured) and this results in torque and speed at the driveshaft of the engine. The speed you can see (it's rotating), the torque is more difficult, but it's there. This torque/speed then has to be coupled to the wheels of the car to get them to move. Being things that rotate themselves, they too will end up with torque and rotational speed, but to get it from the engine, they have to be connected to it by gearing (transmission). Car engines might have lots of horsepower but usually this just means that they give lots of rotational speed and not much torque. Using different sized gears all linked to together the rotational speed can be dialled down and the torque increased (because the engine is supplying a given power at any time, thanks to the equation above if you manage to decrease the rotational speed by applying a sequence of gears the torque must then go up). After going through the gears to the wheel the torque is increased. In terms of a car starting to move, since they are generally pretty high mass the torque needs to be quite high to get any appreciable acceleration (thanks to another equation, the rotational equivalent of force = mass times acceleration).
A "better" engine is then one which is designed to produce more torque for a given horsepower. This is because even though the rotational speed of the driveshaft might well be decreased, it's still going to be much faster than you want the car to go, the torque at the wheels will be higher from the outset (getting the car moving faster) and less gearing will mean less mechanical losses in getting the torque to the wheels.
I have no idea if that answers your question but Happy New Year anyway
windwalker wrote:everything wrote:Can anyone explain it “for dummies”?
Since MA people like to claim physics understanding, maybe someone here can.
The car guys all fail.
If you can get me to understand it, I’ll pay attention to your physics claims. If not, “biomechanics” stays in the same category as woo woo for me as far as the blah blah blah (not anyone’s fault).
seems very straightforward.
If one can not understand something is it their level of understanding or
the material it's self is targeted at a different level.
"physics" itself requires a certain level of understanding not based on experience
seeking to define observations to make them understandable for others regardless
of experience.
everything wrote:
In actual use, if the torque is pretty "flat" but HP increases, why does anyone need to rev this car for acceleration? Is the driver trying to use that peak torque higher in the range (6250ish rpm in this case) so has to rev this car up a bit higher for acceleration? Why can't the shift point just stay at 3-4k rpm where torque is already pretty high before dropping slightly? For example. In either case, after the peak, torque drops, so other than keeping in a gear so the next gear is around the peak again soon, is there any reason to not shift sooner?
Shouldn't people pay way more attention to the torque curve and NOT the HP curve? It seems like that is the case and the marketers and the users themselves are conflating two concepts and metrics. Which would lead me to believe the users also don't really understand the two. It wouldn't surprise me.
For example, a lot of dyno curves for a specific car will show a fairly flat torque curve and a fairly linear HP curve with increasing rpm. But I haven't seen much explanation of that other than circular logic based on a definition of HP and torque and 5252 rpm. There is more HP because there is more rotational speed, but I don't follow the actual meaning of that statement
In actual use, if the torque is pretty "flat" but HP increases, why does anyone need to rev this car for acceleration?
Is the driver trying to use that peak torque higher in the range (6250ish rpm in this case) so has to rev this car up a bit higher for acceleration? Why can't the shift point just stay at 3-4k rpm where torque is already pretty high before dropping slightly? For example. In either case, after the peak, torque drops, so other than keeping in a gear so the next gear is around the peak again soon, is there any reason to not shift sooner?
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