PP Algorithm

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JJSCHMITTY
I was attempting to calculate the PP algorithm, and this is what I came up with.


BALLAST

For every 25 kilograms of ballast/weight, it lowers the PP by 1.5 points. The system rounds up in the PP system.

Power Limiter

Power was a bit tricker, but I figured it out. IF the power curve is exactly 45 degrees, then for every 10 percent you take off of the limiter, it will take 3 pp off. If you take 20% off, then it will take 6 pp off, and so forth. The PP is calculated from the average power, not the maximum power.


AERO- For every 50 aero points that you take off, (with the Red Bull X2011) the pp will decrese by 2 points. This will differ with different cars.

I'll do more work on it some other day, but this is what I have for now. The power limiter was done with the X1 due to it's almost perfectly 45 degree power curve.



I know this isn't much, but if you want to help me out with it you can. This little bit took an hour and a half, so I hope you like it.
 
JJSCHMITTY2000
I was attempting to calculate the PP algorithm, and this is what I came up with.


BALLAST

For every 25 kilograms of ballast/weight, it lowers the PP by 1.5 points. The system rounds up in the PP system.

Power Limiter

Power was a bit tricker, but I figured it out. IF the power curve is exactly 45 degrees, then for every 10 percent you take off of the limiter, it will take 3 pp off. If you take 20% off, then it will take 6 pp off, and so forth. The PP is calculated from the average power, not the maximum power.

AERO- For every 50 aero points that you take off, (with the Red Bull X2011) the pp will decrese by 2 points. This will differ with different cars.

I'll do more work on it some other day, but this is what I have for now. The power limiter was done with the X1 due to it's almost perfectly 45 degree power curve.

I know this isn't much, but if you want to help me out with it you can. This little bit took an hour and a half, so I hope you like it.
Click to expand...

It's different on other cars. I know going from 100-50% power limiter on many cars lowers them nearly 100PP, or nearly 2PP for each 1% power limiter drop.
 
Johnnypenso
It's different on other cars. I know going from 100-50% power limiter on many cars lowers them nearly 100PP, or nearly 2PP for each 1% power limiter drop.
Click to expand...

What was the cars' power curve like and powerband? That has a large amount to do with it. If the car has a really steady powerband, then it will drop a huge amount. Again, the power test was only done on one car, so the results will vary. I'll have to try another car later. Anyway, if the car's powerband is like this
 
To see what Johnny is talking about have a look at the Gillet Vertigo, this car jumps multiple pp and sometimes the pp will go up as you reduce power because of torque going up.
 
I didn't factor torque into the equasion. I haven't gotten that far yet.

Should I try a Cebera Speed 12 for the same effect?
 
You can have 2 identical cars on the same bhp but if one is running different parts to the other then the pp will be different because of the torque. So for example you could have them both on the same pp, one with higher bhp and lower torque compared to the other.

Bhp/torque , weight and aero are the ony factors used for pp, they used to consider tyres but they removed that some time ago.

The whole system doesnt work though, to get a real PP system that does work would take a lot of variables such as the cars chasis, weight distribution (front to back), track being used , tyre size, cars entire drag co effiecent etc. etc. etc. etc. the list would go on and on.
 
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CJSpencer77
To see what Johnny is talking about have a look at the Gillet Vertigo, this car jumps multiple pp and sometimes the pp will go up as you reduce power because of torque going up.
Click to expand...

Exactly. I think this is a bigger undertaking than what the OP understands.
 
God, I bet the algorithm is something like P/(W*T)+A+T=PP

P= Power and so forth. Sorg, have you found ANYTHING like this?
 
CJSpencer77
Bhp/torque , weight and aero are the ony factors used for pp
Click to expand...

Everything else this dude said was pretty spot on, But they also take weight distribution into account.

I think it was the Mazda 787B (1000kg's) I moved some of that weight to the rear (just moved ballast position) and the PP increased.

Considering that 50/50 is always desirable in real life, its weird that it would increase the PP unbalancing the car. Albeit, It did help the car rotate a bit.
 
CJSpencer77
The whole system doesnt work though, to get a real PP system that does work would take a lot of variables such as the cars chasis, weight distribution (front to back), track being used , tyre size, cars entire drag co effiecent etc. etc. etc. etc. the list would go on and on.
Click to expand...

I was writing this down in early days of GT5:Prologue when original PPE system was introduced.

Take a look if you are interested.

LINK: https://www.gtplanet.net/forum/showthread.php?p=3453691#post3453691
 
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rosckolove
Everything else this dude said was pretty spot on, But they also take weight distribution into account.

I think it was the Mazda 787B (1000kg's) I moved some of that weight to the rear (just moved ballast position) and the PP increased.

Considering that 50/50 is always desirable in real life, its weird that it would increase the PP unbalancing the car. Albeit, It did help the car rotate a bit.
Click to expand...

I've also noticed this some time ago. This has happened on a number of, if not all, cars that I have tuned.
 
CJSpencer77
Yh your probably not far off but they dont include tyres in the equation
Click to expand...

Tires are not part of the equation. But I'm sure handling or max G grip is part of the equation somehow, and as far as I know there is no real way to comparably test handling.
 
JJSCHMITTY2000
God, I bet the algorithm is something like P/(W*T)+A+T=PP

P= Power and so forth. Sorg, have you found ANYTHING like this?
Click to expand...

The regression algorithm for all cars MS Excel comes up with is PP = 770.57 * (HP/ kg)^0.359. The sum of all differences between the formula and actual is 0.

Aero is either applied as a power (numerator) or weight (denominator). Ballast would be against the weight, somehow the ballast location is also applied to the denominator.
 
Power is torque measured a different (more useful) way. Torque need not be included at all if the power is considered over the entire rev range, rather than just the peak value. In that sense, it's easy to see how aggregating / integrating the power curve might benefit a "torque-ier" engine producing the same peak power, because it's actually producing more power down low (where there's torque, there's power).

What's important in determining how "fast" a car is in a straight line is to work out the integral power output (i.e. work done) during a run through the gears, at which point you'll notice that gear ratios and shift timings become important, in that they determine where in the rev-range you land after each change.
 
Tires in terms of what they show us (ie. Comfort Soft, Sport Medium, etc.) are not taken into account by the PP system anymore, but there does seem to be some sort of relevance given to a base grip factor of some sort.


rosckolove
Everything else this dude said was pretty spot on, But they also take weight distribution into account.

I think it was the Mazda 787B (1000kg's) I moved some of that weight to the rear (just moved ballast position) and the PP increased.

Considering that 50/50 is always desirable in real life, its weird that it would increase the PP unbalancing the car. Albeit, It did help the car rotate a bit.
Click to expand...

It works basically by adding PP as you add weight to the main drive wheels. That's why it doesn't change much for AWD cars, and why you can make some truly awfully unbalanced cars (mostly seen in FF cars) that have higher PP than one that was set up properly.
 
JJSCHMITTY2000
What was the cars' power curve like and powerband? That has a large amount to do with it. If the car has a really steady powerband, then it will drop a huge amount. Again, the power test was only done on one car, so the results will vary. I'll have to try another car later. Anyway, if the car's powerband is like this
Click to expand...

Any street car pretty much in the 450-600pp range will drop around 100PP using the full engine limiter. I only tested a few in passing, it wasn't a full survey but I doubt there are many exceptions, if any.

Weight distribution can affect PP on some cars and my guess is that PD has programmed for weight over the rear wheels to improve traction and it helps cars to rotate better. In my experience, most cars in GT5 drive better with slightly rearward weight bias, although some cars with extreme front weight bias, still prefer a little front weight bias when tuning.
 
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CJSpencer77
To see what Johnny is talking about have a look at the Gillet Vertigo, this car jumps multiple pp and sometimes the pp will go up as you reduce power because of torque going up.
Click to expand...

Here's my Gillet numbers:
HP kg GT5 PP Formula PP
888 780 671 807
844 780 674 793
799 780 674 777
710 780 668 745
621 780 656 710
533 780 639 672
444 780 615 629

So I figure the Gillett is given an artificially low PP encoded as a default, some kind of a game Easter egg. Once you start adjusting the power or weight the built-in algorithm recalculates the PP properly. There are a few other cars like this, the 2J for example.

They have a large advantage in PP limited events.

And just for info, the ballast changes:

HP kg GT5PP formulaPP
888 820 666 793
888 860 660 779
888 880 657
888 900 654 767
888 940 653 755
888 980 651 744

shifting;

888hp +100kg all to front 643 (PP drops 14)
888hp +100kg all to rear 665 (PP rises 8)

888hp +200kg all to front 631 (PP -26)
888hp +200kg all to rear 661 (PP +10)
 
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