Flaws of the tyre model simulation

ScottPye20

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10,947
Australia
Melbourne
ScottPye20
The way I see it, the friction between tires and track is too low. Tires don't "want" to gain the grip when spinning.
Yeah I don't think the traction increases in a linear fashion like Project Cars 2. In that game the longitudinal grip is higher and more pronounced if you will. For example, the V8 Supercar has more traction than a GT3 car in GT Sport. This is quite true for the first sector on Bathurst.
 

praiano63

Premium
9,000
Brazil
paracuru
praiano63
The way I see it, the friction between tires and track is too low. Tires don't "want" to gain the grip when spinning.
I don't understand why a car have more longitudinal grip one way under braking than the other way acceleration, theoretically it must be the same amount summing the 4 tires , even more for rear propultion cars with a weight transfer to the rear under acceleration that must increase grip to this side... ??!!
 
3,089
Slovakia
Slovakia
dawko-san
Does anybody else think that the biggest part of the problem is that gravity is way too low? Take your car over the dunes at Willow Springs even at moderate speeds and it’s all so far from realism.
Hard to say but it could be a part of the problem. Having said that, low gravity was a problem of GT5 and GT6 as well.
 
142
Germany
Germany
Does anybody else think that the biggest part of the problem is that gravity is way too low? Take your car over the dunes at Willow Springs even at moderate speeds and it’s all so far from realism.

I wouldn't so much call it gravity as the effect of the car's static mass on the tyre model. Bouncing over curbs (last chicane at Nurb GP for eg) most cars look good in terms of air time. However, that visual mass is absent in the grip levels.

There's a also binary "state" problem I believe. I you get into a slide, save it and as a result have scrubbed off speed through a corner you can usually take about as fast as you were going, straighten up and then start to reaccelerate you can sometimes notice that you are *Still* in this slide state. The back goes out again even though you're now travelling much, much slower than the car can travel through the corner as a result of your wobble.

All of this means you can't feel the limit, perform easily around and in the limit or really save yourself once you go slightly past the limit. You just step into the *slide state* and then have to wait until it's over.
Needless to say I pretty much hate the tyre model and physics of this game at slow / medium speeds.

Edit - Just another situation that makes you go hmmmmm. to consider.

The slow left hander 'The Cutting' at mount panorama. You've exited in a gr3 car and are accelerating up the hill to the slight right hander. You give a bit too much gas so the rear wheels lose traction. LOST traction, they have LESS than they just had. And what's the result? The rear starts to come round on you, essentially overtaking the front. How is this even possible? Doe sit suddenly get MORE grip than it had before you LOST grip?

Go get a cheap RWD car and drive it UP an icy hill. Tell me how many time you managed to get the back to overtake the front when you gave it too much gas.

Something super messy going on with the model.
 
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11
Canada
Montreal, Canada
I feel there is a bunch of factors all mixed together that creates a weird car behavior. I admit there is something wrong somewhere about the tires but I cannot pinpoint it. I enjoyed how the cars handled in GT6 and I do also enjoy the handling in gtsport but there is one little thing that annoys me and make the car unpredictable in terms of traction and wheelspin and I think it could be about the differential. I do think that races with fixed settings and BOPs brings unpredictable car behavior because of the fixed differential setting. I feel the differential only works under acceleration which makes it harder for me to control the car in deceleration. I always get the feeling I have to trail brake or keep my foot partially on the throttle while decelerating or cornering otherwise i will get understeer at some point and I do not when. Which makes it unpredictable to me.

When I race in campaign or arcade mode, i set the differential to make it work when decelerating and I love the handling, especially in road cars. Do anyone remember a daily race this summer with the slippery m4 at Willow Springs? I recall some really dislike the handling in this one but I always thought it was feeling right and I could easily control the car in both acceleration and deceleration. I guess i am really used to 2ways differential since GT4 and I tend to loose my landmarks when there is little to no lift-off oversteer.
 
But there was a 200 kg ballast which you can add that fixes this problem or at least to some extent.
I don’t think it will solve the problem because the rest of the simulated models(like tires, suspension) have been modelled from a low gravity reference so adding weight may make things worse in other ways :crazy:
 
4,513
Bulgaria
Bulgaria
I don’t think it will solve the problem because the rest of the simulated models(like tires, suspension) have been modelled from a low gravity reference so adding weight may make things worse in other ways :crazy:
The only way we can understand what will happen is if someone tries it out:)
 
2,209
Canada
Canada
I feel there is a bunch of factors all mixed together that creates a weird car behavior. I admit there is something wrong somewhere about the tires but I cannot pinpoint it. I enjoyed how the cars handled in GT6 and I do also enjoy the handling in gtsport but there is one little thing that annoys me and make the car unpredictable in terms of traction and wheelspin and I think it could be about the differential. I do think that races with fixed settings and BOPs brings unpredictable car behavior because of the fixed differential setting. I feel the differential only works under acceleration which makes it harder for me to control the car in deceleration. I always get the feeling I have to trail brake or keep my foot partially on the throttle while decelerating or cornering otherwise i will get understeer at some point and I do not when. Which makes it unpredictable to me.

You're a genius. This, this is the issue with this game. I cannot coast, at all, or massive understeer.
 
11
Canada
Montreal, Canada
You're a genius. This, this is the issue with this game. I cannot coast, at all, or massive understeer.

If the fixed settings allowed the differential to work under deceleration, we would get a little bit of lift-off oversteer and more control while cornering. It would give a chance to place the car on the right line or make slight corrections in case of a mistake. In my case, I prefer a 2way working differential while racing but I adapt to the fixed settings even if it feels a bit wrong to me. Everyone has a different style of driving and I think differential settings should be left to the drivers preferences. But one thing is sure, the way the differential operates with fixed settings changes the cars behavior in terms of tire traction and wheelspin.
 
2,209
Canada
Canada
we would get a little bit of lift-off oversteer and more control while cornering. It would give a chance to place the car on the right line or make slight corrections in case of a mistake.

I have complained about this since the first day I tried the game, the lack of lift oversteer is absolutely disconcerting. The cars do the opposite and just PLOUGH forwards, which is really wrong.

This really hurts controller users as you cannot really use the best driving style for a controller, Brake hard, lift, flick, point and gas hard. You've kinda got to dive into the corner, avoiding coasting at all costs then rotate with some wheel spin on the way out. It hurts the game imho.
 

Groundfish

(Banned)
4,363
United States
United States
Don’t get where you guys are coming from.
Shift weight forward by letting off and pretty much every car I’ve driven turns in. It’s not like what you say at all there’s no plowing forward. So one, the premise is untrue.
Another point of race driving in general is you shouldn’t be coasting or you are losing time.
 
3,089
Slovakia
Slovakia
dawko-san
Don’t get where you guys are coming from.
Shift weight forward by letting off and pretty much every car I’ve driven turns in. It’s not like what you say at all there’s no plowing forward. So one, the premise is untrue.
Another point of race driving in general is you shouldn’t be coasting or you are losing time.

I'm just going to say that coasting before braking is a useful fuel saving method.
 
798
Canada
Vancouver
Nando_deBem
Don’t get where you guys are coming from.
Shift weight forward by letting off and pretty much every car I’ve driven turns in. It’s not like what you say at all there’s no plowing forward. So one, the premise is untrue.
Another point of race driving in general is you shouldn’t be coasting or you are losing time.

Tenths of second of coasting help a lot. See the whole first sector in Suzuka. Changing directions become a lot easier in the esses.
 

zzz_pt

Premium
8,125
Germany
Porto living in Hamburg
zzz_pt
All of this means you can't feel the limit, perform easily around and in the limit or really save yourself once you go slightly past the limit. You just step into the *slide state* and then have to wait until it's over.
Needless to say I pretty much hate the tyre model and physics of this game at slow / medium speeds.

So, I've been away from GTS for 6 months and this was one of the most frustrating things for me. Basically driving based on visual input and muscle memory other than FFB (apparently is still the same after all the updates). I don't know what PD is doing with the tyre model if basic things like this are not fixed or corrected.

Related to the lack of grip / endless wheelspin issue, which I remember talking about with @Lord Protector way back in January or so, is also the default LSD. Especially noticeable while accelerating out of corners.

I played for a few hours yesterday around Lake Maggiore (probably my fav track and the one where I'm more consistent) and I didn't notice that big of a difference in the tyre model. Cars still spin away round corners if you give too much acceleration input without any FFB coming through the wheel... which means when you see you're spinning it's usually too late because you're relying on visual inputs.

That video comparison between GTS, AC and PC2 is also very telling. The low speed grip is all over the place in GTS and has been since day 1. This not only makes for an unrealistic and sometimes frustrating driving experience, as it also makes the gap between aliens and common folk wider.
 
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3,089
Slovakia
Slovakia
dawko-san
So, I've been away from GTS for 6 months and this was one of the most frustrating things for me. Basically driving based on visual input and muscle memory other than FFB (apparently is still the same after all the updates). I don't know what PD is doing with the tyre model if basic things like this are not fixed or corrected.

On the lack of grip / endless wheelspin issue, which I remember talking about with @Lord Protector way back in January or so, is also the default LSD. Especially noticeable while accelerating out of corners.

I played for a few hours yesterday around Lake Maggiore (probably my fav track and the one where I'm more consistent) and I didn't notice that big of difference in the tyre model. Cars still spin away round corners if you give too much acceleration input without any FFB coming through the wheel... which means when you see you're spinning it's usually too late because you're relying in visual inputs.

That video comparison between GTS, AC and PC2 is also very telling. The low speed grip is all over the place in GTS and has been since day 1. This not only makes for an unrealistic and sometimes frustrating driving experience, as it also makes the gap between aliens and common folk wider.
Hopefully I get a chance to throw my 5 cents on this topic at the World Tour :cheers:
 
2,209
Canada
Canada
Don’t get where you guys are coming from.
Shift weight forward by letting off and pretty much every car I’ve driven turns in. It’s not like what you say at all there’s no plowing forward. So one, the premise is untrue.
Another point of race driving in general is you shouldn’t be coasting or you are losing time.

We are playing a different game. I simply CANNOT get these cars to turn in in SPORT mode with no tuning. So, so, so much understeer. I expect that when i lift off the brake the rear should become a little unstable, enabling turn in. it just doesn't, the car feels exactly like it does on the gas just slower.
 

Groundfish

(Banned)
4,363
United States
United States
We are playing a different game. I simply CANNOT get these cars to turn in in SPORT mode with no tuning. So, so, so much understeer. I expect that when i lift off the brake the rear should become a little unstable, enabling turn in. it just doesn't, the car feels exactly like it does on the gas just slower.

Maybe you could describe one specific track car turn combo.
Then look at inputs and discuss.
 
2,209
Canada
Canada
Last corner, Maggorie, fastest way through is to take it very early and use the inside rumble strip. But my god, i brake, i lift and she just will not turn the way you'd expect, so much understeer.
 
662
United States
New Jersey
Do anyone remember a daily race this summer with the slippery m4 at Willow Springs? I recall some really dislike the handling in this one but I always thought it was feeling right and I could easily control the car in both acceleration and deceleration. I guess i am really used to 2ways differential since GT4 and I tend to loose my landmarks when there is little to no lift-off oversteer.

IMO that was an AWFUL track/car combo. I HATED that race.
 
96
United States
United States
Butaketsu-C130
Last corner, Maggorie, fastest way through is to take it very early and use the inside rumble strip. But my god, i brake, i lift and she just will not turn the way you'd expect, so much understeer.

What car are you driving? I can take it just fine with a stock N200 SW20 and a Gr. 2 RC F.
Understeers massively with anything FWD though, I will give you that much.
 

Groundfish

(Banned)
4,363
United States
United States
@NevilleNobody

It’s easy to unbalance the car there and lower your effective limit imo. I enjoy that track but in comparison to many I kinda suck at it Timewise.
Some of the original tracks have that baby crown in the middle track such that the outside half puts you a touch off camber like that one. Turn 4 Maggiore is similar imo as well as many others imo. I notice there on that last turn for myself in any car if it’s unsettled in the entry phase I won’t get the best exit. I feel like you have to be delicate on the controls there to keep balanced and get the car set nicely coming off brakes super smooth and not much steering input as the car sets into the corner entry.
I’m no expert, but I can see many examples all over of people driving the same cars/tracks/setups in this game much faster than others so it’s not the game causing it.
 
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59
Canada
Canada
Hoping the new update will fix the low speed grip problems. It's almost kind of frustrating and it seems like GTS is the only game to have this problem.
 

zzz_pt

Premium
8,125
Germany
Porto living in Hamburg
zzz_pt
Hoping the new update will fix the low speed grip problems. It's almost kind of frustrating and it seems like GTS is the only game to have this problem.

Low speed + low acceleration grip problem.

It's so stupid and frustrating to see a race car with racing tires spin endlessly in 3rd gear with the throttle input bar bellow 30%...
 
142
Germany
Germany
Anyone read / see / notice any different in the v2.8 update? Let us know here.

edit: because I sure as darn it don't notice any difference
 
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