HUGE flaw in HP/torque curves

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Natural Newbie

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First let me explain what physics lay out in real life.

All engine curves from every and any type of engine, at 5252 RPM, HP and torque will be equal to each other.

Torque will always be higher than HP at 5252 RPMs or lower. And HP will always be higher than torque at 5252 RPM or higher.

The formula is a constant. What's important here is that HP is related to torque and speed of the engine. The 5252 is derived from a compound of constants and conversions. More info can be found at this very helpful site

Here is a simple mathematical proof I put together for you all.
hptrq.jpg


Here are a few examples of HP/torque curves
HondaTRX450R-StockDyno.jpg


2003SVTCOBRAbhpchart.jpg


Here are a few examples of THE MANY cars in GT4 that have in-correct HP/torque curves. The red lines on the engine curve are in increments of 1000RPM (to the nearest pixed anyway :) )

Dsc00970.jpg


Dsc00965.jpg

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Dsc00966.jpg


Dsc00967.jpg


Yes, the max HP and max torque points may be correct (and have the correct RPM to go along with it) but the curve and intersection points are NOT correct.

How could Kazunori Yamauchi let this slide? :crazy:

It seems to me the cars behave according to the curve also, which makes some of them perfom rather oddly.

This could have gone in the bug forum but I thought this issue stood out from the rest. Thanks for reading and I will be glad to hear your input!
 
The torque and power curves DO intersect at 5252.

You are simply misreading the graphs. Look at the two examples you posted above. Look at the left X-axis power scale. Now look at the right X-axis torque scale. Note that the SCALES are DIFFERENT on both of them! :)
 
aklucsarits is right, the graphs arent the best, but they do look about right. you need to read the different scales seperately, not compare them.
 
Gran Turismo has always been weird like that ... That's probably because they designed the game for ps and kgm instead of hp and lb-ft ;)

ps and kgm don't exactly scale well together, so a different scales are needed for each to show the curve ...

1 kg-m = 7.23 lb-ft ...
1 ps = 0.98632 hp ...

So it's kind of difficult when the value of torque is 1/7 while the value of torque is slightly higher ... If they used the same scale, it would show very little variation in the torque curve since it would be so compressed ...

BTW, HP = Torque*RPM/5252.113122 ;)

Also, I'm really hating those scales in GT4 ... They should have markers at every 10 hp/lb-ft so it's easier to calculate force ... Oh well, I guess you can just figure out gearing by the area under the power curve ...
 
You can make any graph intersect at any range depending on what scale you were using for each value...

Therefore this topic is 100% meaningless...

As Disreali once said... "There are Lies, Damned Lie and Statistics"

C.
 
*ignore me I can't read*

guys, look at that last one again. He is showing you that all the real ones intersect at around 5252rpm. Now, look at the one for the Integra Type R. That intersection is a little higher than 5252, more like 7500. The truck is around 4500 maybe.
 
as stated above, the graphs are in fact correct.

it is very common to have dynos in the real world with different HP & Torque scales.

btw, how did you pull that screen up? is there any page you can view the cars specs on?
 
cchhrriiss1982
guys, look at that last one again. He is showing you that all the real ones intersect at around 5252rpm. Now, look at the one for the Integra Type R. That intersection is a little higher than 5252, more like 7500. The truck is around 4500 maybe.
Click to expand...

I did. Now you look at it again :P

the dyno graphs are scaled so that peak torque and peak HP are at the very top of the graph.
 
Greyout
btw, how did you pull that screen up? is there any page you can view the cars specs on?
Click to expand...

In the setup menu, move the cursor to the top where you can choose the A,B,C settings. Then move to the right past "C" and press X. The closest thing to a specs page i've found is the page you get when you try to sell a car, though it's missing some pieces of information (NA/Turbo) and is often incomplete.
 
Natural Newbie
First let me explain what physics lay out in real life.

All engine curves from every and any type of engine, at 5252 RPM, HP and torque will be equal to each other.

Torque will always be higher than HP at 5252 RPMs or lower. And HP will always be higher than torque at 5252 RPM or higher.
Click to expand...
Not really, the curves can actually intersect anywhere you want, depending on how you choose the scaling of the axes. Only if you use use hp and lbft (which, US aside, are quite obscure units to most of the world) and use the same scale for power and torque, the curves will intersect at that point.
 

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