Okay, so I need a little help here understanding the basic principles behind an accelerating car, mainly the importance correlation between acceleration, gear ratio, horsepower and torque.
I mean, as I understand, the best acceleration is achieved at the peak horsepower point, but why the fuck do people supply me with torque charts to measure how well a car accelerates then?
Cars and Physics3World
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primaltheory
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primaltheory
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maximum thrust is achieved at peak torque not peak horsepower
Here's a very good article on Analyzing hp vs. torque
Here's a very good article on Analyzing hp vs. torque
Horsepower = Revs x Torque
Petrols generally rev much higher than say a diesel, therefore needs less torque to produce the same output. A diesel revs much lower therefore needs lots of torque to produce the same power.
I have a diesel, and it produces twice the torque of a friend of mines car, yet their both roughly the same speed because his is petrol and revs more.
Petrols generally rev much higher than say a diesel, therefore needs less torque to produce the same output. A diesel revs much lower therefore needs lots of torque to produce the same power.
I have a diesel, and it produces twice the torque of a friend of mines car, yet their both roughly the same speed because his is petrol and revs more.
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AmIdYfReAk
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AmIdYfReAk
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AmIdYfReAk
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allright, if you want to talk about torque.. you should take a look at this..
http://video.google.com/videoplay?docid ... 3077382755
if all else fails, just give er.
http://video.google.com/videoplay?docid ... 3077382755
if all else fails, just give er.
AmIdYfReAk wrote:allright, if you want to talk about torque.. you should take a look at this..
http://video.google.com/videoplay?docid ... 3077382755
if all else fails, just give er.
Okay I still can't wrap my head around one thing:
Take a big truck that has lots of torque. Take a small jap car. Put said jap motor in big truck. To make the truck go, you would have to rev the small engine incredibly high to gain the same amount of torque. Seems to me like making it accelerate depends on torque*revolutions, so HP is the determening factor here. No?
At the same time, torque would basically be number of revolutions that the crankshaft makes, but (with a constant ratio of transfer losses between the gearbox etc) should still be the number of revolutions the truck makes, e.g. higher torque would make it accelerate.
(edit) While thinking about it with a clearer head, it would still seem that torque makes the car move. So ideally the car accelerates the best when it has max average torque, correct?
Take a big truck that has lots of torque. Take a small jap car. Put said jap motor in big truck. To make the truck go, you would have to rev the small engine incredibly high to gain the same amount of torque. Seems to me like making it accelerate depends on torque*revolutions, so HP is the determening factor here. No?
At the same time, torque would basically be number of revolutions that the crankshaft makes, but (with a constant ratio of transfer losses between the gearbox etc) should still be the number of revolutions the truck makes, e.g. higher torque would make it accelerate.
(edit) While thinking about it with a clearer head, it would still seem that torque makes the car move. So ideally the car accelerates the best when it has max average torque, correct?
related note.. anyone got that video of the ridiculously overmodded car at 1000s of BHP on a rolling ramp surrounded by fans? I can't remember the car, think it had GT40 stripes, but it was on the ramp, and it spins up and just keeps getting louder and louder and louder and then they show you the output graph at the end.
EDIT: I think it was a corvette
EDIT: I think it was a corvette
"Maybe you have some bird ideas. Maybe that’s the best you can do."
― Terry A. Davis
― Terry A. Davis
Taken from this article:Scarface wrote:maximum thrust is achieved at peak torque not peak horsepower
Here's a very good article on Analyzing hp vs. torque
"The trick to a strong powerband is to reach peak torque at a relatively early point then hold that consistant torque output to get a good horsepower number. It's really a compromise of having a big peak number and reaching peak torque at an early point, since low end and high end power often don't mix."
"In the high RPM's it doesn't take much torque to make more horsepower, so when dealing with motors of similar peak HP numbers, you can bet the one with the larger peak torque number is going to have the stronger powerband."
