Obviously they don't, as can be verified by a quick look at the dyno chart I provided some posts ago... No intersection at 5250rpm, since the dyno run was performed using nm instead of ftlbs to measure torque. And as you can see, the vertical scales are the same on the left and the right side so there's no trickery when it comes to that. Power and torque are not magically equal at 5250rpm, that only happens when you measure power in hp and torque in ftlbs and it is due to the relationship between the units of measurement.

I've already provided you with two separate graphs showing the differences in visual praphic representation when you use different units of measurement, they should be plenty of proof that what you are saying is wrong. A 30cm dick is roughly 12 inches long, yes. But the graphic representations when inserted in the same graph are different since the numerical digits in front of the units of measurements are different. Not because the size is different, the units are.

If you're baking a cake that calls for 1 cup of sugar, you can substitute 0.24 litres of sugar instead since it's the same amount measured using a different unit of measurement. 1 is obviously a larger number than 0.24, so when you insert those numbers side by side in a stack diagram the columns will be of different height. Not because the amount of sugar is different, the units of measurement are. Just like nm and ftlbs are different, they both still measure torque and can be translated back and forth between each other but the numerical digits in front of the units of measurement will change by doing this, just like the 1 before the cup of sugar became 0.24 in front of the unit litre. And when you insert numbers of varying size in a chart, they end up higher or lower in accordance with the vertical scale.

Please tell me you get it now?

 

I think there's something wrong about the chart. The RPM relationship between HP a d TQ does not change based on the unit of measurement. Power is achieved at a certain RPM no matter the unit of measurement. Its simply a mathematical constant.

 

I can't even tell if you're seriously not getting it or just trolling at this stage... Look, there's nothing wrong with the chart. Convert NM into ftlbs and you'll get your magic intersection, like I've been saying from the beginning. If you wanna get into the maths behind it all, the relationship between the units of measurement comes down to the fact that torque is calculated by a force multiplied by a distance and in the case of ftlbs these units of measurement are feet and pounds. Horsepower is calculated by the formula hp=Fd/t where F=force measured in pounds and d=distance measured in feet. That's where the relationship between the units of measurement for hp and ftlbs of torque comes from, they are both based off of feet and pounds. That's why this magical intersection at 5250 happens when you use these units of measurements. NM has got nothing to do with feet and pounds and that's why it doesn't work when the torque is measured using this unit of measurement.

Ok, now I'm done. If you haven't got it by now... Best of luck to you.

 

He doesn't.

 

Could you please tell me, was there something wrong with my explanation? I mean, English isn't my first language so maybe I simply explained it badly... I don't think I screwed up though.

 

I feel the same way. Do the RPMs change when you convert from imperial to metric? Because there's only 1 horizontal scale, RPMs are RPMS, and its neither imperial or metric.

 

Keith why you playing?

The RPM/HP scales have not changed and it doesn't matter. What changed is the Dyno sheet is displaying NM rather than Torque...
Look at the Gold lines. At 5200 RPM the HP is approx 130 HP and the NM is approx 175. Take 175 and put it in a NM to Torque (foot Pounds) convertor and guess what, the new value = 129.07 TQ.
Take 129 TQ and place it on the graph is it's basically crossing over the HP line.

 

Listen to Ip. The RPMs stay the same. It's only the heights of the curves that change due to the fact that 1nm is not equal to 1ftlb of torque. When measured in hp and ftlbs, power and torque are equal at 5250RPM due to their inherent relationship (both being calculated using feet and pounds) and that's why the curves cross. But since 1ftlb=1.356nm, the curves won't look the same and won't intersect at 5250rpm. Not because there's a difference in torque, but because the units of measurement are different. Whatever the torque is at the RPM where torque and hp intersect when torque is measured by ftlbs, the numerical value will be different when converted into nm and the curves will no longer intersect.

Let's say 100hp and 100ftlbs of torque intersect at 5250rpm on a dyno chart. If you convert the torque into NM instead, you get 100*1.356 = 135.6NM @5250rpm. The power curve will still be down at 100, but the torque curve at 5250rpm will be at 135.6 instead and so the two curves no longer intersect at this RPM. They are still the same torque, just like a 12 inch dick is as long as a 30cm one or 1cup of sugar is the same amount of sugar as 0.24 litres. They are just measured jusing different units, and the measurements can be different. a 12 inch dick isn't bigger than a 30cm one, but 30 as a number is bigger than the number 12. Likewise, 135.6 is inarguably a larger number than 100 and therefore the torque curve will no longer intersect the power curve at 5250rpm but will instead be above the power curve when the unit of measurement NM is used instead of ftlbs.

You have to have understood it by now, pretty please?

 

I get what you're saying, but this is the way I look at it: There is a mathematical relationship between HP and TQ, I'm sorry if you don't like that. You can construct any whacky chart you want, but my point always been is strange to do that and makes them difficult to compare. I don't understand why tuners construct charts that way, but whatever.

 

Same chart two ways may help
BTW, the formula we refer to : Power is equal to Force (in foot pounds) times RPM, then divided by 5252, is why the sheets cross at ~5200. It's just the math used.

Typical sheet, SAE corrected with foot pounds on left and horsepower on right.

Same bike run, represented as N-m on left and horsepower on right