M8 Dyno Numbers
#611
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90anlu92 (04-24-2022)
#612
Has exactly zero to do with the HP/TQ measurement units (ft lbs vs nms). RPMs are RPMs. They dont cross at 5252 because the left and right vertical scales are different. To me it's mystifying to me why anyone would configure a chart that way.
#613
Wrong. Has exactly everything to do with units of measurement. The NM numbers will be higher since 1ftlb = 1.356 NM and therefore the torque curve will stay above the power curve at 5250. If we look at JED Polands chart, torque at 5250rpm seems to be about 175NM (roughly). That's about 129 ftlb of torque, so if the chart had been using this measurement instead the lines probably would've intersected as his HP at 5250 is around 130.
I'll post my own chart since that too was measured in NM. As you can see, the lines never intersect. However, if we convert the NM at 5250rpm (looks to be about 155NM) to ftlb of torque we get 155/1.356=114 which closely matches the bhp at that rpm meaning the curves would intersect had another measurement been used.
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JED POLAND (10-27-2022)
#614
You sir are correct. NM and ftlb are just different ways to measure torque, they can be converted to and from one another just like cups can be converted into litres and vice versa. Metric vs imperial.
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JED POLAND (10-27-2022),
lp (04-24-2022)
#615
Wrong. Has exactly everything to do with units of measurement. The NM numbers will be higher since 1ftlb = 1.356 NM and therefore the torque curve will stay above the power curve at 5250. If we look at JED Polands chart, torque at 5250rpm seems to be about 175NM (roughly). That's about 129 ftlb of torque, so if the chart had been using this measurement instead the lines probably would've intersected as his HP at 5250 is around 130.
I'll post my own chart since that too was measured in NM. As you can see, the lines never intersect. However, if we convert the NM at 5250rpm (looks to be about 155NM) to ftlb of torque we get 155/1.356=114 which closely matches the bhp at that rpm meaning the curves would intersect had another measurement been used.
I'll post my own chart since that too was measured in NM. As you can see, the lines never intersect. However, if we convert the NM at 5250rpm (looks to be about 155NM) to ftlb of torque we get 155/1.356=114 which closely matches the bhp at that rpm meaning the curves would intersect had another measurement been used.
There is something not right about the above chart. I think he set the scales improperly or something but they should absolutely cross at 5252 rpms
It's not any hotter if you measure the temperature outside by F or C. Its the same amount of heat.
Its the same whether you measure in imperial or metric. The RPMs dont change just because you are measuring the power using imperial or metric. A dyno run is a dyno run.
It's like saying your pee pee is bigger because 30cm is a larger number than 12 inches.
Before you watch the video, just look at the screen preview. If this was a measurement of your height over time, would the line be different because you are measuring in inches or centimeters? No.
Last edited by Keithhu; 04-24-2022 at 12:49 PM.
#616
Wrong. RPMs is RPMs. Its a mathematical truth that no matter what the unit of measurement of power, the lines will cross at 5252, its just that simple. It doesnt matter if you cut a pie into 10 pieces of pie, or 5 pieces of pie, you have the amount of pie.
It's not any hotter if you measure the temperature outside by F or C. Its the same amount of heat.
Its the same whether you measure in imperial or metric. The RPMs dont change just because you are measuring the power using imperial or metric. A dyno run is a dyno run.
It's like saying your pee pee is bigger because 30cm is a larger number than 12 inches.
https://www.youtube.com/watch?v=lt7iUBE3_AE
It's not any hotter if you measure the temperature outside by F or C. Its the same amount of heat.
Its the same whether you measure in imperial or metric. The RPMs dont change just because you are measuring the power using imperial or metric. A dyno run is a dyno run.
It's like saying your pee pee is bigger because 30cm is a larger number than 12 inches.
https://www.youtube.com/watch?v=lt7iUBE3_AE
These three dicks are the same size, but since they've been measured using different units of measurement they look like they aren't. Just like a torque curve using NM will be higher on the graph compared to the same torque measured in ftlbs.
Get it now?
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JED POLAND (10-03-2022)
#617
Before you watch the video, just look at the screen preview. If this was a measurement of your height over time, would the line be different because you are measuring in inches or centimeters? No.
https://www.youtube.com/watch?v=lt7iUBE3_AE
https://www.youtube.com/watch?v=lt7iUBE3_AE
That's a person growing at a steady rate from nothing up to 200cm tall (roughly 79 inches) over the time of 20 years represented by two curves, one measuring cm and one measuring inches. Same height measured using two different units looks different on the graph since the left bar is just a numerical value. It's pretty obvious when you think about it. 1 inch is not equal to 1cm, so you don't grow an equal number of inches as centimetres even though you've gained a certain height. Those two units are just different ways of measuring that same height.
Last edited by 90anlu92; 04-24-2022 at 01:21 PM.
#618
Yes, it would. Here's how that would look:
That's a person growing at a steady rate from nothing up to 200cm tall (roughly 79 inches) over the time of 20 years represented by two curves, one measuring cm and one measuring inches. Same height measured using two different units looks different on the graph since the left bar is just a numerical value.
That's a person growing at a steady rate from nothing up to 200cm tall (roughly 79 inches) over the time of 20 years represented by two curves, one measuring cm and one measuring inches. Same height measured using two different units looks different on the graph since the left bar is just a numerical value.
If you had ONE dyno run, and converted the numbers from ft to nm, the RPMS would be the same. Changing the power measurement scale does not change the RPMs at which the power is achieved.
#619
Honestly, it's not that difficult... If you haven't gotten it by now I'm not gonna bother explaining it further. Anyone else wanna take over?
Last edited by 90anlu92; 04-24-2022 at 01:36 PM.
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JED POLAND (10-27-2022)
#620
It's the relationship between the units of measurement that matters. You can measure things using different units of measurement, and that will impact how the curve looks. Measuring power using hp and torque using ftlbs you get an intersection at 5250, measuring power using hp and torque using NM means you don't. Measuring power using KW (1hp=0,7457kw) and torque using NM the curves still wouldn't intersect at 5250 since the power curve would be even lower and the two curves would be spread even further apart. Look at my dyno graph again. Power at 5250rpm is roughly 114 hp, or 85kw. If I were to insert that number in the graph instead of using hp the distance up to the torque curve would increase, it would not bring the two curves together.
The RPM would stay the same, the numerical digits in front of the measured units wouldn't since 1 NM is not equal to 1 ftlbs and so the height of the curves would change which means power and torque curves don't cross.
Honestly, it's not that difficult... If you haven't gotten it by now I'm not gonna bother explaining it further. Anyone else wanna take over?
The RPM would stay the same, the numerical digits in front of the measured units wouldn't since 1 NM is not equal to 1 ftlbs and so the height of the curves would change which means power and torque curves don't cross.
Honestly, it's not that difficult... If you haven't gotten it by now I'm not gonna bother explaining it further. Anyone else wanna take over?
I'm not trying to be a d1ck, I enjoy these kinds of discussions, and if and when I'm proven wrong, I will gladly admit it, but the point in RPMs at which power is achieved does not change, and I am not taller because I am 177.8 CM vs 70 inches.