Broken physics for some cars (MR) still as of Version 1.22?

[elston87]

Last night (as of this post) I decided to replay Gran Turismo 6 again and do a few laps around some courses with specific cars. Two of the many cars I drove, however, had terrible handling issues that don't seem to have ever been fixed. I remember reading about this problem forever ago but I can't pinpoint the exact cause. But basically:

Are MR-drivetrain cars broken in this game? I recently drove the Citroën GT by Citroën Race Car and the Formula Gran Turismo. I took the Formula GT to Tokyo R246 and the car was having issues staying planted while taking the high-speed corners. Meanwhile I took the Citroen to Apricot Hill Raceway and that car was having issues on low-speed corners. I feel like there's this immediate snap-oversteer effect where the grip of the front tires just dies all of a sudden. Applying any sort of throttle will cause this behavior, and in the case of the Citroen it wouldn't matter if you applied throttle or not. In any case, a car with as much downforce as the Formula GT never felt planted; you can't hit the apexes of the high-speed corners because the snap oversteer happens and you lose complete control of your car.

I remember this being a huge issue with the game a while back, particularly with the Audi R8 LMS and its variants, but I never looked into it back then when I actively played GT6. My recent memory thought that they had fixed these issues even in the latest update, only for me to do these past few time trials with horrid results. Skid Recovery Force seems to help the Formula GT a bit when taking high-speed corners, but is useless for the Citroen's problems. Traction Control doesn't matter, either, because it's like a switch- once the snap oversteer happens, the switch effectively turns your grip off and kills you, sending you into out of control.

If you want to replicate what I was experiencing, you can do the following:

• Take a Formula Gran Turismo to Tokyo R246; use whatever driving options you like but keep Skid Recovery Force Off, and then try to take any of the high speed corners and observe what happens.
• Take a Citroën GT by Citroën Race Car to Apricot Hill Raceway and take the hairpin corner after the long straight in the middle of the course. Observe what happens as you try to enter the corner.

From what data I was able to gather off of this forum, this has something to do with camber being broken? And that setting camber to 0.0 will (mostly) fix the handling issues for these cars? This means though that a good number of cars featured in this game are now unstable out of the box without mandatory tuning, when I think that these cars shouldn't require tuning just for them to be stable. Something's definitely off here, but I can't pinpoint what.

If anyone can summarize the issue here with the physics, or link to a few individual posts that shed brighter lights on the issue, I would greatly appreciate it, because I'm trying to wrap my head around it as of now...

 

[nostradavor2]

I play much more gt5 than gt6 and when I decided to go through gt6 again I noticed huge difference in physics. Didn't try cars you mentioned but I remember that difference in handling of Ferrari 458 surprised me. I did almost all endurance races in 5 with it on different tyres and almost never lost control (note that I never use SRF in any car). When I used it in 6 I remember it suddenly lost a grip in high speed corners and I was spinning few times until I kind of adjusted to driving it. What was weird for me is that car handled betternon sport soft tyres then on racing hard, after the switch ai almost never had that problem. I don't know if physics are broken because I don't really take corners doing 240 kmh in real life but it actually makes sense that grip gives out suddenly and car snaps if you push car and tyres beyond limits so its probably more correct in 6 than in 5.. IMO people are not use to that kind of car behavior but for me it's logical that you'll have the grip until you push tyres too hard in corners.. I don't think that you could do fast corner in MR car doing 240 kmh trying to push it little bit more and than have just little oversteer that you can correct.. no.. the car will snap and you'll die.. So I don't know really. Maybe @skeagracing who has lot of real life racing experience can answer your question better.

 

[smoothbore12]

In real life driving and of course racing i think that things are quite more complicated but the good part is that we don't need to know so much for ride ( safely ) and for racing either.
I didn't run the cars that @elston87 write above since i just read it but during playing gt6 in our hub especially at no tune ,i find cars with way more grip than i could imagine or cars with excellent stock behaviour.
For certain programming a car behaviour for a game can vary depending to the values that you put at it in many areas.
For sure they are simulators that are used from top F1 teams and perhaps in others ( but i don't know that) that cost millions and with thousands parameters to adjust .
No game can be so realistic with so many cars and perhaps they will need years for it .
I don't know exactly how many parameters PD use for each car but for sure you can mess things or make them a lot better from what it should be.
Its different factors that make the warning point wide or short till car loose grip.
Can be in snap or not .
There was a very interesting post in gt6 threads which someone made a program that could change many aspects at cars behaviour but i must shearch to find it .
I was looking at it during Christmas holidays.
Anyway if someone feel ready to extend his tyre knowledge ,here is a small guide
http://racingcardynamics.com/racing-tires-lateral-force/

 

[eran0004]

MR cars have always been hard to drive in GT6, there is something in the setup or physics that make them oversteer easily.

I wouldn’t say they are broken, with a bit of suspension tuning you can make them easier to handle, and some MR cars can be fantastic to drive (for example the Ferrari 430 Scuderia).

If you don’t like to experiment with suspension tuning you can adjust the weight balance by adding some ballast to the front of the car.

 

[elston87]

I should have mentioned that most (if not all) of the MR-drivetrain road cars feel quite fine; it's only most of the MR-drivetrain race cars that feel broken.

I recently did a test with the Formula Gran Turismo from Version 1.00 to the latest version of the game. I can't remember when the physics changes were finalized (mixed resources say either V1.09 or V1.15, but it's still uncertain) and they're two different cars. On Version 1.00, the FGT is still a handful to drive but the car remains planted even when taking the high-speed turns at Tokyo R246. Brake very softly for just a bit, throttle full-off, hit the apex, throttle full-on, and the car remains planted throughout the entire turn. On Version 1.22, however, you simply can't do the same; the car's front tires just all of a sudden lose all of their grip, and the car is drifting at 160mph+ into a wipeout. It's like driving on an oil slick; that's the best way I can describe it. I would think that understeer would occur once you get back on the throttle when taking a high-speed turn like that, not immediate oversteer and losing all of your grip and wiping out. It feels like there's absolutely no downforce anymore. It just doesn't feel right.

Both tests were ran with the car in its default configuration, driving options being ABS 2, TCS Off. Between the two versions, the parameters are different, because whenever the physics model was last updated, the parameters for most of the cars were also changed to suit the updated physics model, so between the two versions, the cars are not running the same tuning. Even then, using the car's V1.00 parameters on V1.22 didn't do much of anything. Only with the use of a tune that I found on this forum (and Skid Recovery Force) does the car feel (mostly, but not completely) like it does on V1.00. I feel as if the Lotus 97T is more stable than this car running the same driving options as well.

My guess is that whenever the physics were updated, the parameters of the cars just don't quite fit the actual physics model, even if they got updated as well. I don't know for sure; I don't even know for sure when the physics were updated last in GT6. Either way, the FGT just doesn't feel right in V1.22. Hitting the apexes on a high-speed course like Tokyo R246 and just all of a sudden having the grip just die out at 160mph when getting back on the throttle- I can pull it off all day on V1.00 because the car behaves like I expect it to, but not here on V1.22.

 

[Draggon]

What was weird for me is that car handled betternon sport soft tyres then on racing hard,

Yep, I thought the same thing. That last physics update really messed things up. They did the same thing in GT Sport. The most recent update has induced considerable off-throttle oversteer.

I'm curious to know if you are on a wheel or use a controller. I've read that some wheel users in Sport don't have the oversteer problem.

 

[nostradavor2]

Yep, I thought the same thing. That last physics update really messed things up. They did the same thing in GT Sport. The most recent update has induced considerable off-throttle oversteer.

I'm curious to know if you are on a wheel or use a controller. I've read that some wheel users in Sport don't have the oversteer problem.

wheel mate.. I'm useless with a controller

 

[Thematic]

It now occurred to me that since there has been many observations about strange handling at low speeds or tight turns, the car parameters, hidden or vis/adjustable, are probably "tuned" to the intended racing performance. So going from stock setup three or more tyre grades "up" or "down" or adding a lot of performance improvements may compromise any accuracy there was to begin with, the severity depending on the chosen car.

 

[DioEmsti]

I have mixed feelings about GT6 physics, while I generally like them better than GT5, the cars feel like they carry less weight and momentum, I also find the need to be more careful with the throttle in GT5 with some racing cars while in GT6 they are way too easy to drive.. On the other hand some like the Ferrari F40 felt horrible until I balanced the weight with ballast options, and changed the suspension settings and tires, it made a huge difference.

 

[elston87]

Still haven't investigated the changed physics yet. Sometime next week I'll be combing over the GT6 versions to see when they changed, specifically with the Formula Gran Turismo.