Tuning for oversteer 2.09

[CSLACR]

I made a video of max/min vs min/max yesterday on the test course (not even having seen this thread), showing how the min/max had more rear grip and the max/min had better top speed still, as always, but unfortunately my phone doesn't really let you know it's upside down or not...

 

[MrGrado]

Did this last month...

https://www.gtplanet.net/forum/showthread.php?p=7676177#post7676177

{Cy}

You did that in an online lobby before 2.09 right? so that's irrelevant now.

Just had a look at some of your "tunes"...

Cizeta V16 '94

600 Performance Points
812 Horsepower
1550 Kilograms

Ride Height: 29 / 32

Sooooooo... a car with serious oversteer, and you RAISE the entire car even more (when most cars in real life are lowered to improve handling or stability) and you have rear ride height higher than front...

Pfffffffffftt - troll-lol-lol-lol-lol-lol-lol-lol

That was tuned before 2.08 so that is irrelevant now. Go look at a ruler that has mm on it. 3mm difference front to back isn't going to make much difference either way to handling and as was just posted, ride height has an effect on straight line performance

 

[CyKosis1973]

You did that in an online lobby before 2.09 right? so that's irrelevant now.

Seriously, dude, seriously..?? Come on, you've done nothing, what so ever, other than sit there and try to tell me that everything is different to how I've demonstrated it is.

If you're going to stand by your above statement, then you're admitting that ride height was reversed pre 2.09, but now, miraculously, it's not. Why don't you, instead of being a belligerent arsehole, devise a test that I can carry out that demonstrates that nose down/tail up ride height produces oversteer?? Something along the lines of what I've already done, three columns, firstly the inputs I need to make, secondly your expected outputs and thirdly I'll fill in the actual outputs. If the expected and actual outputs match, then you're right, ride height works exactly like it does in real life, if they don't, then I'll have wasted more of my life proving the same thing ... again...

{Cy}

 

[MrGrado]

Take the Zonda C12S tune I made or S2000 tune I made to the Nürburgring, do some laps and save the fastest replay. Do the same with the front raised 10mm. Watch both replays and take note which replay contains more counter steering.

Or provide me a FR or MR tune that is not completely bogus, that is on the verge of having a little bit of oversteer in it that I can apply the same test to.

 

[CyKosis1973]

Take the Zonda C12S tune I made or S2000 tune I made to the Nürburgring, do some laps and save the fastest replay. Do the same with the front raised 10mm. Watch both replays and take note which replay contains more counter steering.

Or provide me a FR or MR tune that is not completely bogus, that is on the verge of having a little bit of oversteer in it that I can apply the same test to.

Use the RX8, stock with adjustable suspension, that has exactly what you want, neutral with mild oversteer. Or I can run an S2000 under the same conditions.

Running a car that has already been tuned isn't really fair, there are too many other variables that may effect how the car handles. It was requested of me that I re-run my initial RX8 test, but without making any weight changes. I didn't do that at the time, so maybe I'll repeat with stock weight.

EVEN/EVEN - Default setting
MIN/MAX - Nose down/tail up
MAX/MIN - Nose up/tail down

These will be the inputs I make, all I need from you is what output you'd expect. If we can find a convinient time, I'll hook up with you online and we can run the tests in tandem. If we both make the same inputs and get different outputs, then this game* is more broken that I first thought...

{Cy}

* - And let's just remember this, it is a game, which means it has very little bearing on real life...

 

[rams1de]

Cy, I think you might be surprised at just how little difference those settings make.

I tried playing with extreme ride height and spring rate settings on an otherwise stock BMW Z4 M at Tsukuba and Motegi and there was no drastic change in the car's behaviour. It may be that courses with elevation changes and banking will have a different outcome but I'm getting better results from tweaking wheel alignment and dampers settings.

 

[MrGrado]

I tested ride height changes on the RX8. I fitted sports hard tires and Custom suspension. I used 1.0 / 1.0 negative camber and 0.00 / 0.00 toe settings, all other settings were default. I drove at the Nürburgring in offline practice.

Even ride height:

I ran this first and did just 90% of a lap, the car had some oversteer but ran wide with understeer in some places also. Running wide might have just been driver error.

MAX/MIN:

More stable than MIN/MAX on corner entry, it has a more stable feel overall than MIN/MAX. This would not really oversteer, rather understeer, with a few exceptions.
This tune could get into a small drift on corner entry of Aremberg (the first hairpin) but far less than with MIN/MAX. MAX/MIN could oversteer on corner exit of Wehrseifen and Steilstreckekurve that MIN/MAX did not (basically out of low speed corners under power). The stable corner entry that MAX/MIN gives is especially good at Breidscheid and Hatzenbach-Geschlangel (down hill, high speed braking areas). MAX/MIN also could lose the rear with bumps from heavy curbs easily.

MIN/MAX

This tune was unstable in some braking areas, as mentioned and did not go into oversteer on corner exit in low speed bends but overall this tune had less understeer. I did not need to lift off the throttle from understeer like with MAX/MIN. MIN/MAX is better mid corner and on change of direction, it could also hold through the inside of sweeping bends better. It basically understeers less and oversteers a little more.

 

[Adrenaline]

MAX/MIN:
This tune could get into a small drift on corner entry of Aremberg (the first hairpin)

MAX/MIN could oversteer on corner exit of Wehrseifen and Steilstreckekurve that MIN/MAX did not.

MAX/MIN also could lose the rear with bumps from heavy curbs easily.

MIN/MAX
...did not go into oversteer on corner exit

I can't tell if you're serious or not?
The car understeers, except that it drifts on entry, is loose on exit, and loose on bumps. You reversed the ride heights, and the car no longer oversteers on exit.

As far as I can tell, you're proving our point, not disputing it.

 

[MrGrado]

Yeah, find me a track that is all curb and no bitumen and all 2nd gear corners and I will lower rear ride height for oversteer.

 

[dr_slump]

Ride Height

High:

+ higher longitudinal g-force
+ wider threshold
+ less sensitive on bumps
+ more room for other adjustments
+ more controllable/forgiving
- lower lateral g-force
- spongy behaviour
- bad tire wear due to chronic tendency to skid
- hates abrupt driving/weight shifting​

Low:

+ higher lateral g-force
+ more stable inside the working range (w/o real negative effects such as huge bumps etc.)
+ better response
+ more direct behaviour
- lower longitudinal g-force
- critical over huge bumps
- snappish
- less forgiving/controllable if driven over the limit
- more digital (reaction) feeling due to an abrupt limit​

Now combine these above to your min/max and max/min settings - shouldn't be too hard.

I must say I personally don't like the min thing, simply because from my experience the absolute lowest height value often doesn't work as well as a just slightly increased amount. I recommend to do testing with an increased height such as (as example) min+5.


Testing was done with a premium 91 RX7; stock except fc-suspension and sport exhaust, sports hard tyres, online, real physics and no aids except abs 1. The track of my choice was the gorgeous trial mountain circuit.



EDIT: Oh and if someone can't see (to say it nice; calling ignorant would be the other option) the difference between longitudinal and lateral then please ignore this. It's better for you and for us all then.

 

[rams1de]

^^^ You can call me ignorant if you like Dr Slump.

But, please explain what you mean by "wider threshold".

Thanks

 

[dr_slump]

the magnitude or intensity that must be exceeded for a certain reaction, phenomenon, result, or condition to occur or be manifested: nothing happens until the signal passes the threshold | [ as modifier ] : a threshold level.

• a level, rate, or amount at which something comes into effect