1.6 - Issues with grip

1.6 - Issues with grip

 

The problem is that you might have saved a setup in the past. Whatever you do, everytime you enter the setup menu it will always load a saved setup for whatever reason. You can hit reset, adjust a few values, go to the pit, the moment click on setup again - boom - the safed setup is loaded again. This is a huge issue if you still have some setup from older patches.

So with each patch that changes physics/tires it's wise to go into your documents AMS2 folder and delete all setups (I think the file type is .svm) of classes that got adjustments

 

I want to support the "reset" solution/issue here! Haven't touched AMS2 for a long time. Wasn't driving before either, but did a couple of hot laps some time ago. Has been racing a decent amount of iRacing recently.
I watched Daniel Morad's video about GT3 physics and from what he said it's that the GT3s have a decent amount of grip and the thing which happens first when accelerating on exit is rather understeer out of corner than spinning out (because the car has enough grip, front tires get less weight and here we go). That is actually how it feels after latest tyre update in iRacing. And you can steer during braking too, as long as you don't lock up completely.

I was super excited about the new NBR25 update and wanted to test it in AMS2. I hopped in and the GT3 were undrivable.

• even at light braking, losing the rear and sliding
• in fast corners at Nord I had to turn the wheel much more (like 30° more than usual) in a weird way than the racing line, if that explanation makes sense, so the tires would make a lot of noise, but this was the only way to keep the car on track.
• and then losing the rear and spinning when going on throttle almost in every corner (cold or hot tires)
• the gears were totally different to the "usual" GT3 setup too
• I remembered the FFB to be much better too, it was very weak and underwhelming

It felt so frustrating and unrealistic (especially the part with the wheel rotation (animation was the same as my wheel btw.)) that I started googling and ended up here.

I went to setup, did "reset", saved this default setup just to be sure, and it was like night and day.
I have to test it further, but the FFB alone is already super strong and full of details, and the weird wheel rotation is fixed too. The car seems much more controllable and the gears are set up as I'm used to from other sims and GT3 "default"
I think it must be a sort of bug with the setups or something! But if you don't know I try it that way, the driving is terrible. Unfortunately, I didn't manage to record this, I'll do if I come across it again.

 

This GT3 tire thing is not related to setup.... it is not related to 'temporary track temperature'... it is IN the tires!
It would not matter what you do in a setup WHATSOEVER, you can never make a tire be a 'slippery thing'. For example, if you ran very low ('zero') rear wing, then the rear would be loose - even very loose.... but it won't alter HOW the tires ACT. It would only affect high speed cornering.
But these tires ALLOW drift during high speed cornering. An optimum Slip Angle of 10degrees or more! (Motec logging backs this up).

The same for track temperature, or even tire temperature. It happens a tall track temperatures, Then, if it is a 'bug' in how the tires act according to track temperature - you still would not get an optimum high slip angle, you would just get a tire that EXCEEDS grip easier - sooner. The same for a tire temperture issue.

This problem is the TIRES (their physics parameters) ALLOW their behaviour. This unrealistic behaviour.

This doesn't mean their can't ALSO be other issues in the game... but those other issues are not the cause of this 'drift racing GT3' tire issue. Those other issues would affect rear AND front tires. But the front tires act fine (enough). Their grip levels and behaviours per slip etc are 'believable' and within an expected range of tolerance (accuracy).

 

I agree that the tires seem to provide too much optimal slip angle on the GT3 classes and in some others too, like on LMDh. I don't have any hard data to back this up though, but at least here: https://suspensionsecrets.co.uk/tyre-slip-angle/ it says "Most racing tyres at the maximum lateral G often achieve up to 7 or 8 degrees of slip angle" (no idea is the tires modelled for AMS2 in these classes hugely different from this in IRL)

I'm not even sure are the tires really that peaky after you go past that optimal slip angle either, but is that correct or not depends also on the brand of tires they are trying to emulate as the characteristic of the tires seem to vary a lot in IRL, just look at the video from Coach Dave about latest tire developments for iRacing and LMU and how he gives description about differences in tires IRL between manufacturers (

)

BUT the default setups (and a lot of setups in general) are also often problematic, usually in such way that you get oversteer easy on corner entry and for some, also oversteer when you go on throttle seems to be a issue (not usually for me, but I'm used to modulating throttle and not have it as an ON/OFF switch with TC to protect). Even with the big slip angles, the rear get's very loose on the default setups on corner entry and makes it feel that the tire are more unforgiving that they really are, especially when trying to trail brake deep and rotate at the same time (and especially if it's tighter downhill corner). This is very much of a setup issue, those setups require specific type of driving to work, which don't include trail braking deep into the corner (instead brake earlier, come of the brakes early, then turn and go on some throttle very early and use the rotation from the rear to help). With different kind of setups, you can notice the slip angles more and benefit from them with less risk of losing it. NOTE! those setup issues usually start to come out only after the tires are in more optimal temps, so maybe on 3rd or 4th lap onwards if the track is warm enough and the front tires start to grip up more (before that it's usually either more balanced over understeer on corner entry)

In addition to that, there seems to bug too that affects some people (never had that myself) mentioned by Renato.

ps. it doesn't mean the cars aren't fun to drive on AMS2, quite the contrary. To compare, I find the GT3's on LMU dull as hell, with chronic understeer and feeling weak on throttle even though it might be closer to IRL behavior (though I don't think it's there yet either and neither do the experts like Dave Perell on the video). We also have to remember, LMU is modelling different brand of tires and even different GT3 regulations, so we cannot exactly expect the characteristics of the handling to be the same as it would be wrong then too

 

I did a video on this using telemetry and I found that AMS2 wasn’t allowing too much slip

 

I wouldn't trust my own driving to produce the best examples on how much slip angle the tires are able to provide as it's clear that the fastest people out there seem to be able to push car clearly more than I can and extract more from the capability of the tires. Like here, in your video, you didn't seen to get more that about 7-8 degrees of slip, but PeterV seems to claim to see 10 degrees or more even.. Not sure how scientific those tests are.

I guess we are talking actually more about cornering stiffness and how peaky it is as described in this picture, where green is example of "road tire" and yellow of a peaky racing tire.
(source:

) but at least in my experience, the peak seems as it would be more flat and the maximum slip angle you still have optimal grip quite big, so maybe something like the pink curve I drew here:



There is cliff there eventually and it's sharp, but after the peak you still have a lot of grip beyond that "dull" peak before it drops sharply. I don't have any data to back this up, this is based more on how it feels myself and how it looks when watching the driving of some really fast drivers on AMS2 on GT3, LMDh and the like.

If you have setup like the default ones often are, it feels more peaky than the tires are and it seems to be related to car pitching, load getting too much to the fronts in the expense of the rears. With more balanced setup, you don't reach that cliff nearly as easily and can really push to a point that it feels like overdriving to extract lap time.

To be clear, I don't know is it actually off that much, at all or a lot. I just have noticed that the better I get, the more it feels I can abuse this with still quite big marging for error (in some other sims, like LMU, the window in which you are in optimal slip angle feels a lot smaller, even if the drop off going past it isn't as steep as it was just before 1.0)

I think the tire wear properties are still lacking quite a bit and even if you could drive IRL like this, you would kill the tires really quickly by doing so, but in AMS2, the endurance tires can take so much wear that you never really need to think about that (I think this applies to all tires actually, even the F-ultime tires last way too much unless you lock up). You can use probably setup options (more locked diff, more toe etc.) that IRL would cause actual problems in tire wear that contributes to the problem.

I would to see some really in depth analysis of this from somebody with a lot of knowledge of these things and time to spend.

 

So why not having a better default setup for gt3 gen2 ?

 

It depends on "who" is making the default set ups, and their definition of better.
I think it would be safe to say that the default set ups for GT3 G2 are not "balanced" in the general sense. But with some small set up tweaks and adjusted driving techniques, the driving can feel more balanced.
Some might say less exciting, some might say more controlled. Depends on who you talk to.
But for those who just want to hop in with the default and go (without tweaking), they might be in for a wild surprise.

 

We'll better is a bit subjective and in what way? A lot of it is track dependent too.

I do think the setups could be much more safe, even if those would be slower than current ones, meaning a bit less emphaisis on rotation (so more understeer and less risk of oversteer on both corner entry and exit) to provide more stable starting point that wouldn't be as frustrating for new players who especially can struggle with the corner entry oversteer and drivers coming from something like ACC and LMU where you tend to brake late and use trail braking for rotation. I'm sure it would make the cars seem a lot less slidey as well to many.

That new GT4 Alpine that many seem to enjoy a lot... that has different default setup from a lot of other cars and I think that actually plays a huge part why people tend to enjoy it (the GT4 Aston is quite opposite with it's default setup, but that too can be adjusted to be more in the Alpine style).

 

One thing is for sure, the current defaults are very different that the defaults you find in sims like ACC and LMU (where the defaults can be much more understeery to a point it's frustrating)

 

The GT3 G2 defaults could probably be described as Expert Aggressive, so at least users should know what their getting into to.
Maybe there should also be a Balanced Safe set up offered, but would require more work for no sales return, so probably not going to happen.
All I do for a safer set up is drop some clutches, raise some EB, and enter corners with less trail braking. And of course a custom FFB file that lets you really feel the grip loss/recovery better.

 

I mean this is the setup that everyone first try. And they expect to be perfectly balance without big risk.

 

Without any description of what the GT3 G2 default set up "type" is, you are left to discover it on your own.
Expecting it to be perfectly balanced and safe seems logical, but in fact it's not.
Like if you order a steak in a diner, and don't specify how you want it cooked, who knows what you'll get on any given day with any given cook.

 

Gt3 gen2 is the class I am the more confortable. Gt4 or GT1 are more sensible with oversterr in corner entry. Gt3 gen2 could loose the rear if I don’t pay attention.

 

Just a quick reminder as I don't know if it has been addressed in any way, but a lot of the default setups (in a lot of the GT3 both gens) have very high engine braking, if you're having issues with snap oversteer under braking or throttle lift-off, I would suggest reducing this. I tested this and proved that the Nissan (at the time) had no difference on the engine braking setting, compared to the Porsche gen1 GT3 which went from 2 seconds slower than the Nissan for me, to being on par once I reduced the engine braking. Tweaking the engine braking for me transformed all the "undriveable" cars to being perfectly reasonable to handle. This is obvious a separate issue to the slip angle debate, but definitely a factor for those who are struggling in testing to maybe experiment with.