The meaning of stability on the settings sheet?

easygtsport11

easygtsport11

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Over on the left of the settings sheet you can see the values for stability, low speed and high speed. I'm wondering if anyone knows what it means when these values increase or decrease during tuning. Any help would be appreciated, thanks.
 
easygtsport11
Not even a little brother. They simply pose a question about the values. Thanks for the reply tho.
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Well no, it's not an answer. But I've been trying to get a grasp on this as well.
Basically all we can do is learn from whatever others have found. That guy is like us, trying to figure it out lol. And of course the people replying to him are also more of us.
When I was actively trying to mess with this, I found that when I used a 4wd and evened the weight 50/50, and adjusted the suspension settings as close to a good weight transfer as possible.... that was as close to zero's I got. And I have no idea if any of that had anything to do with it, was just playing guessing games to see what altered it and what didn't.
But there are game mechanic professionals among us. One of them must have gotten this down to a science by now, but I haven't seen anything posted yet.
 
"...that's as close to zero's I got"

That's interesting. I'll have to toy with that on a 4WD car. Thanks.

Yeah, as it is right now I have no idea what it means when those values increase or decrease. But I'm guessing your sacrificing speed for stability here. And if I can get more speed, all the better.

I really should have played around with this a little more. Just posting in hopes somebody else knows something.

Thanks again
 
The way I interpret the Stability section is that these numbers relate to how the overall balance of the car will be at low speeds and high speeds. I've seen these numbers go positive (for oversteer), neutral, and at it's highest, at least -1.00 (for understeer). Adjusting the front and rear downforce changes these values and so does the following (see below):
  1. Ride height
  2. Dampers (compression and expansion)
  3. Spring frequency
  4. Camber
If you want a bit of a safety net at high speeds, I would ensure the range between the two numbers are as wide as possible (e.g. -0.30 at low speed, then -1.00 at high speed) or at least the high speed stability is close to -1.00. This will make the car understeer at high speed (not necessarily a bad thing). If these two values are close to each other (e.g. -30 for low speed and -.31 for high speed) this will make the car neutral at high speed. The car will either understeer or oversteer depending on the driver's input, the track conditions, wind, and whatever bumps, dips, curbs the driver runs over. Basically making the car less predictable or in some instances unstable.

This has been my experience with higher powered rear wheel drive cars on street soft (SS) tires.
 
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Ive been doing alot of tuning with stability and turning lately i got my ford gt lm test car to a -0.56 low speed ..It might be a bit of a glitch theres a very tiny sweet spot with the camber and rear wing that it drops 8pp..
 

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It's an indicator of your car's behaviour while turning at low (probably 40 mph) and high (150mph) speed.

Bear in mind that the number assumes that you are holding this speed perfectly, so that means you aren't accelerating or decelerating, as we all know if you accelerate at low speed with a high power car it is going to significantly affect handling but that is not what is being measured here. We can prove this by adjusting the setup values for Acceleration and Braking Sensitivity in the LSD, and observing that no difference is made to the the Stability values.

It's impossible to know for sure exactly how it is measured but here is how it is probably done: The game simulates your car turning at full steering angle, with constant low throttle applied to keep the speed set exactly to 40/150mph. The number that is recorded is a measure of how much understeer or oversteer the car has at those speeds while neither accelerating or decelerating. The range of values is -1.00 to 1.00.

If the number is a negative value, it means that your car has more grip at the rear than it does at the front, and as a result it will understeer when travelling at a constant speed. If the number is positive, it's the opposite, it means the rear of the car has less grip than the front and it will oversteer while travelling at a constant speed. If the number is zero, it means that the handling is neutral.

It is not a measure of how much your car can turn, that is measured within the Rotational G section. More specifically, Stability measures the behaviour of the car's handling, while Rotational G measures the performance of the car's handling.

It's important to note that there is no 'best' number for Stability, as I said it measures the behaviour of the car while you are not accelerating or decelerating. If you have a powerful RWD car you will obviously find that you can induce oversteer by applying throttle while turning, in this kind of situation you will most likely find that having the car's Stability at a negative value will allow you to apply more throttle while turning than a neutral value for Stability. If you had a FWD car though which is going to understeer under acceleration, you would want to have Stability values closer to neutral or maybe even positive.

TL;DR the closer the value to -1.00, the more your car naturally understeers. The closer to 1.00 the more it naturally oversteers.
 
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MrMattAdz
If the number is a negative value, it means that your car has more grip at the rear than it does at the front, and as a result it will understeer when travelling at a constant speed. If the number is positive, it's the opposite, it means the front of the car has less grip than the rear and it will oversteer while travelling at a constant speed. If the number is zero, it means that the handling is neutral.
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Uhhh don't you have that backwards? rear more grip should be understeer, front more grip should be oversteer.
 
Hey thanks for a response MrMattAdz.

"TL;DR the closer the value to -1.00, the more your car naturally understeers. The closer to 1.00 the more it naturally oversteers."

I'll keep this in mind when tuning. As I cannot prove it really wrong or really right.

"It's impossible to know for sure exactly how it is measured"

It's frustrating that they put this value where they put it and made it so obscure. Between accel and rotational G you would expect these values to translate into time on the track. But I still can't make any distinctions in performance, yet.

thanks again for your response.
 
Yes, what would be needed for a really good and safe setup would be a meaningful diagram and not just 2 values, because as already written, we only have 2 static values with fixed speeds and 3 information about potential G forces, although not even here it is clear which axis is being simulated. Because with one thing I'm sure that the values for the front and rear are different for many RWD cars.

Which would also work if we could choose the speeds ourselves when tuning to see how the car behaves at speed X.
 
Setup up your trans until you are happy with the way the gears operate, THEN, set the initial torque on your lsd until it reads the lowest number possible for the neutral low speed. After that it's just moving spring rates, ride heights and what ever else until that number gets as close to zero as possible. Mine is +0.01. can't seem to get it any better.
 
easygtsport11
Over on the left of the settings sheet you can see the values for stability, low speed and high speed. I'm wondering if anyone knows what it means when these values increase or decrease during tuning. Any help would be appreciated, thanks.
Click to expand...
This helped me a little. Oops forgot to include the link and don't know how to delete yet but got it in the next one...
 
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easygtsport11
Over on the left of the settings sheet you can see the values for stability, low speed and high speed. I'm wondering if anyone knows what it means when these values increase or decrease during tuning. Any help would be appreciated, thanks.
Click to expand...
This helped me a little
 
After reading your post. I decided to try out what you stated. I am not a tuner by no means. Actually I get my tunes from this forum. So to get to the point I looked at the most stable car that I have which is the Road Version Tomahawk. I looked at the values that were listed for stability which are Low Speed -0.74, High Speed -1.0. I then took a GR.3 C7 and determine the base tune and saved it. Then I created a new tune and adjusted things until I had as close to the same stability numbers for low and high speed as possible. The values I changed on the C7 were height, rear roll bar, negative camber, toe angle, LSD Initial and Braking. The final numbers on the C7 are -0.67 low speed and -1.0 High speed. I then tested both setups on a time trial at spa-francorchamps. The average time decrease between the base and the tuned was 4 seconds. I know it wasn’t a perfect test, but I can say that you guys are defiantly going in the right direction.
 
bambam26
After reading your post. I decided to try out what you stated. I am not a tuner by no means. Actually I get my tunes from this forum. So to get to the point I looked at the most stable car that I have which is the Road Version Tomahawk. I looked at the values that were listed for stability which are Low Speed -0.74, High Speed -1.0. I then took a GR.3 C7 and determine the base tune and saved it. Then I created a new tune and adjusted things until I had as close to the same stability numbers for low and high speed as possible. The values I changed on the C7 were height, rear roll bar, negative camber, toe angle, LSD Initial and Braking. The final numbers on the C7 are -0.67 low speed and -1.0 High speed. I then tested both setups on a time trial at spa-francorchamps. The average time decrease between the base and the tuned was 4 seconds. I know it wasn’t a perfect test, but I can say that you guys are defiantly going in the right direction.
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Ah, I made the same mistake at first but you don't actually want to be trying to get cars to the same Stability values. If they happen to work by coincidence that's fine, but the 'right' Stability for each car is determined more by stuff like power, weight balance, driven wheels etc.

Power and driven wheels are maybe the most important stats to keep in mind, while you apply throttle you are changing the Stability of the car. If you apply throttle with a RWD car, you are moving the Stability values closer to +1.00, and while you apply throttle with a FWD car you are moving them closer to -1.00.

If I have an 800bhp RWD car I am going to want Stability settings that are strongly biased towards understeer at high speed, because the moment I try and apply full throttle mid corner, the Stability of the car is going to drastically change. But if my car only has 200bhp I don't have to worry about it as much, I still want understeer bias but because it has less power the Stability won't be affected as much, so I will probably be faster with a car that has less understeer bias.

Always remember as well that the Stability numbers only go up to 1.00 on paper, but they can actually be much much larger than this. This is another reason not to try and match Stability numbers, once you get to 1.00 it's impossible to know what the number actually is, it could be 1.01 or it could be 3.00.

This stuff applies to brake balance too: If your car has understeer bias you probably want to move brake bias towards the rear. If the car has oversteer bias you want to move the balance forwards to make braking into corners more stable.
 
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MrMattAdz
Power and driven wheels are maybe the most important stats to keep in mind, while you apply throttle you are changing the Stability of the car. If you apply throttle with a RWD car, you are moving the Stability values closer to +1.00, and while you apply throttle with a FWD car you are moving them closer to -1.00.
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Moment...

-1 means the car tends to understeer, values close to 0.0 are neutral and values close to +1 are oversteer.

So RWD vehicles with a lot of power at high speeds should preferably have understeer as -1 than neutral or even oversteer with +1.

An FF or AWD, on the other hand, is usually easy to drive with a certain tendency to oversteer.



However, there seems to be a pitfall with the G force. If I get it right, there is only one G value for a speed X. Apparently, this does not refer to the whole car, but to the axle with the highest grip.

If this is indeed the case (and it appears to be so after some testing) then the more disparate the axles, the harder it is to tune. And it is absolutely necessary, especially with RWD vehicles, to first tune the vehicle so that only the rear axle has grip and not the front axle, only in the second step do you lift the front axle as far as possible from the grip until the G Force shifts back into negative.

If you now e.g. If the downforce for the front axle is further increased, the displayed G force can increase again, only this time it seems to affect the front axle and it can lead to the rear axle losing grip without being able to see it.
 
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MrMattAdz
This stuff applies to brake balance too: If your car has understeer bias you probably want to move brake bias towards the rear. If the car has oversteer bias you want to move the balance forwards to make braking into corners more stable.
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Also, adjusting the Braking Sensitivity value of the fully customizable differential will effect stability under braking. The higher the number, the more stable the car will be under braking and off throttle. Yet if it's set too high, the car will lack rotation under braking and off throttle.
 

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