Gran Turismo 7 Physics

[Firestone]

Uhm… GT5 did, GT6 did, pCARS2 did and I’m sure many other hardcore sims do.

And by the way, the "dynamic" dry racing line in GT7 is a total scam. It’s completely pre-scriped, it doesn’t reflect the actual path that cars take, I tried this several times on several tracks.

Not according to Jimmy Broadbent. He's been calming video after video that it's the most detail recreation of wet weather out of any sim. I trust his opinion more than an forumer.
Give examples of what you tried and your tests rather than calling it a scam.

 

[Firestone]

Did you read that post fully before you decided to use a strawman argument?

At no point was it said that it's impossible to loose a car, simply that it's nothing like as easy as it is in GT7, but once again we have real-world experience being pushed aside in favour of confirmation bias.

Now I did watch it, just to see what's going on, and for the first ten incidents we have the following:

1. Out-braked themselves in a corner notorious for it
2. Understeer
3. Race car - not relevant to this, but they also out-braked themselves
4. Race car - not relevant to this. but two cars off on the same corner in the same way? Most likely dropped oil or similar
5. Understeer
6. Offline in the wet
7. Race car - not relevant to this, but blatantly unbalanced from ridding the curb
8. Engine blowout
9. Way to fast trying to keep pace with the 'vette, braked far too late and the curb didn't help either
10. Can't actually see the start of the control loss so impossible to say

So based on a quick review of your video evidence it would seem that most accidents don't occur in the way they can with some road cars in GT 7.

As it stands right now in GT 7 we have a situation in which race cars are more progressive on the limit than the majority of road cars. This runs counter to reality, as with stiffer suspension, less progressive tyres, lower ride-height, lower Polar Moment of Inertia, etc they have all the ingredients (and this isn't a subjective view, this is the objective laws of physics) that should make them less progressive over the limit than just about any road car.

I'm yet to see any of those saying that the snap oversteer we are finding in many road cars (many of them also cars known for being progressive in reality) is harder to manage than in race cars that should 100% be less progressive. The closest I've seen is some utter nonsense about soft suspension causing more load transfer (not the way physics works kids, not at all).

So those extoling the virtues of this physics build, please explain it to me? Why are the road cars less progressive than race cars, as this runs counter to reality? No vagaries, the actual physics (even in basics) of why this is, because as it stands right now, one of these is wrong!

They updated the physics model and the road cars are more progressive. There were a lot of factors that could possibly lead to the older model. Most road cars have stability management, so most people don't even know when you enter a slide, your car is actually braking your wheels to maintain stability. I was just at an autox session with my car and felt the car pulse the brakes to prevent me from spinning out. Cars will also dial back throttle without you knowing it. It may very well be they originally had the physics model as to simulate cars with no assists. This is a good example from the FRS when you activate the "pedal dance" to turn off all the stability management

To note, this car has as only 135ft-lb (183Nm) of torque to the wheels and notice how easy it snaps and easy to light his tires up.
To note, race cars can snap hard if they go beyond their slip angle. It happens all the time.

 

[ScottPuss20]

I drove the Ferrari F40 on Monza yesterday and it felt just fine. But you know one car that's surprised me the most? The C6 Corvette ZR-1. With a rear wing and diffuser, it drives extremely well. I highly recommend it.

 

[wheelhp]

He has been praising the wet weather the whole time he has been playing and said it is the best execution of any sim.

aaaand Now I've lost you. That was quick

 

[HyperSpeeder]

I drove the Ferrari F40 on Monza yesterday and it felt just fine. But you know one car that's surprised me the most? The C6 Corvette ZR-1. With a rear wing and diffuser, it drives extremely well. I highly recommend it.

The F12berlinetta is a 691 bhp, front engine, RWD monster and not too difficult to drive either.

 

[graesand]

Dd

To note, this car has as only 135ft-lb (183Nm) of torque to the wheels and notice how easy it snaps and easy to light his tires up.
To note, race cars can snap hard if they go beyond their slip angle. It happens all the time.

Im not sure we are getting this.
Let me think out loud for a sec.

As far as i know, the gearbox translates torque and angular velocity from the engines output shaft via a system of gears to the rear wheels.

The gear ratio for first gear (which the person in the video used?!) In a gt86 is 1:3.63

The torque sent to the rear axle is then
183nm * 3.63= about 700nm

Then if im not further mistaken, the actual wheel diameter and rubber thickness plays some role in what actual torque is sent to the ground and ofcourse it also has an effect on acceleration. The actual force sent to the contact patch should be fairly easy to calculate by knowing diameter. Then the compound probably has a coefficient of friction thats temperature dependent, which im not at liberty to even think of at this hour, but im sure thats fairly easy to grasp too.

Lets guess the diameter is 18 inches, we take the radius and convert to metric, because only people who measure things with their thumbs use imperial.

9 inch * 2.25 = ~20cm = 0.2m

The definition of torque is

M=F*R

So

F=M/R

Then the force at the contact patch if only applied to one wheel is

F=700/0.2=3500N

3500N is in this shoddy calculation the equivavalent for all purposes to ca 350kg.

Thats the force excerted in first gear if its to only one wheel, perpendicular to the axis, or tangential to the wheel, as you whish, but certainly paralell to the ground.

I bet you already figured if the diff is locked then it would be 350/2 per wheel. Thats still 175kg force tearing that poor tire in the direction the rotation wants.

Afaik gt86 isnt known for their beefy tires, but for their excellent character at and beyond the limit. Im lead to believe its largely down to using tire width and diameter suitable to the power and a predictable chassis setup, coupled to low CG body.

Its 4 am and i could just be dreaming I got learnt at school, lets hope i dont have to delete this in shame in a couple of hours when i smell coffe again.

 

[extreme car]

They updated the physics model and the road cars are more progressive. There were a lot of factors that could possibly lead to the older model. Most road cars have stability management, so most people don't even know when you enter a slide, your car is actually braking your wheels to maintain stability. I was just at an autox session with my car and felt the car pulse the brakes to prevent me from spinning out. Cars will also dial back throttle without you knowing it. It may very well be they originally had the physics model as to simulate cars with no assists. This is a good example from the FRS when you activate the "pedal dance" to turn off all the stability management

To note, this car has as only 135ft-lb (183Nm) of torque to the wheels and notice how easy it snaps and easy to light his tires up.
To note, race cars can snap hard if they go beyond their slip angle. It happens all the time.

Notice how very linear and controllable the car is when he turned everything off or pedal dance, not snappy like in gt7.

 

[wheelhp]

I really don't know if you are really listening and understanding to what he says. He said the wet weather driving in GT7 is amazing and it isn't "a million percent realistic" in regards to the lines the AI are taking since they were taking the dry lines rather than the wet lines. At 11:19, I listened to what he was talking about a few times over and what he was saying before that time stamp and I remain correct. He was exemplifying that the cars in front cutting a path in the water allowed his car to have more grip. As soon as he got out front, that cut path was no longer there and he was struggling more for grip. He has been praising the wet weather the whole time he has been playing and said it is the best execution of any sim.
Even in previous video at Tsukuba in wet weather, he discovered he could steer lock his front tires to approach a corner that helps turn in which is a tactic that is used in karting irl. He just been saying the we weather driving has a ridiculous amount of detail.

okay wow, still confusion and wild glossing over? I'll give you the benefit of the doubt... I'm gonna just attempt to just translate, yeah, his entire sentences then, from the muzzled captions, cause there's still confusion. okay wow, didn't think I'd need to do this but.. Here. we. go:

I've done my best to translate exactly from timestamps to 11:12 to 11:44 just for you

"right now there's not really a line anywhere it feels like.. and that's something that maybeee i think that GT needs to do a little bit better, is it needs just to have that dry line there underneath the surface of the water for you to- Avoid... ...because right now I can drive on it pretty much and be okayyyy.. i say that, i've just tagged a bit of water there... oh my god come on Jimmy, survive it... survive it..."

As heard in this video:

Gran Turismo 7 Physics

After a few days of exclusively using race cars I’m starting to really enjoy my time with gt7. To be honest I couldn’t abide the road car grind. Found it dull as dishwater and quite frustrating. But the group cars are actually incredibly rewarding to drive. It’s clear now that they’ve put a...

www.gtplanet.net

If anyone else wants to translate from 11:12 to 11:44 be my guest. I reckon I'm closest
I happen to pride myself in my understanding of the English language... LOL

 

[Firestone]

aaaand Now I've lost you. That was quick

I don't know what you mean, but what I'm saying is an undeniable fact.

 

[wheelhp]

I don't know what you mean, but what I'm saying is an undeniable fact.

okay then... I'm doubly sure whatever you think you're saying that's undeniable fact is less fact than a scientific fact.

 

[oqvist]

How is it with tire wear does it exist? I am doing the career so only done up to 5 lap races. I haven´t seen the tire bar changing colours or anything so tire wear at least in the career is not there? No reason to go racing hard instead of racing soft for better pace late in races

 

[LittleBobcat]

How is it with tire wear does it exist? I am doing the career so only done up to 5 lap races. I haven´t seen the tire bar changing colours or anything so tire wear at least in the career is not there? No reason to go racing hard instead of racing soft for better pace late in races

you can check about tyre wear/fuel usage in the briefing before race.
If you want to get some feeling about tyre wear/fuel usage, try some endurance races in mission challanges, such as tsukuba 30 laps or high speed ring 30 minutes mission, quite a bit fun for me with dynamic weather.

 

[Firestone]

Dd

Im not sure we are getting this.
Let me think out loud for a sec.

As far as i know, the gearbox translates torque and angular velocity from the engines output shaft via a system of gears to the rear wheels.

The gear ratio for first gear (which the person driving used?!) In a gt86 is 1:3.63

The torque sent to the rear axle is then
183nm * 3.63= about 700nm

Then if im not further mistaken, the actual wheel diameter and rubber thickness plays some role in what actual torque is sent to the ground and ofcourse it also has an effect on acceleration. The actual force sent to the contact patch should be fairly easy to calculate by knowing diameter. Then the compound probably has a coefficient of friction thats temperature dependent.

Lets guess the diameter is 18 inches, we take the radius and convert to metric, because only people who measure things with their thumbs use imperial.

9 inch * 2.25 = ~20cm = 0.2m

The definition of torque is

M=F*R

So

F=M/R

Then the force at the contact patch if only applied to one wheel is

F=700/0.2=3500N

3500N is in this shoddy calculation the equivavalent for all purposes to ca 350kg.

Thats the force excerted in first gear if its to only one wheel, perpendicular to the axis, or tangential to the wheel, as you whish, but certainly paralell to the ground.

Its 4 am and i could just be dreaming I got learnt at school, lets hope i dont have to delete this in shame in a couple of hours when i smell coffe again.

Yeah, that is my point (I graduated a ME 10 years ago, it's still fresh in my mind. This is sophomore level dynamics). 183nm is insignificant compared to what's out there. Without electronic aids, it's not farfetched for a low power car to snap into oversteer which a lot of people thing is foreign with production cars. 2nd gear, which people are experiencing is still near 300nm of torque!

 

[Firestone]

Notice how very linear and controllable the car is when he turned everything off or pedal dance, not snappy like in gt7.

He definitely snapped in the video

 

[Firestone]

okay then... I'm doubly sure whatever you think you're saying that's undeniable fact is less fact than a scientific fact.

Ok man. You can continue to tread cognitive dissonance. He's very clear what his position on the game is.

 

[wheelhp]

Ok man. You can continue to tread cognitive dissonance. He's very clear what his position on the game is.

No actually. Jimmy's very clear in what he said. Drop the insults and just try to translate exactly what he said in that moment that I've taken the time to do if you want the truth.

 

[Firestone]

No actually. Jimmy's very clear in what he said. Drop the insults and just try to translate exactly what he said in that moment that I've taken the time to do if you want the truth.

I can't with this. lol. Believe whatever you want. Everyone else will understand what he is explaining.

 

[wheelhp]

I can't with this. lol. Believe whatever you want. Everyone else will understand what he is explaining.

What I've translated is here https://www.gtplanet.net/forum/threads/gran-turismo-7-physics.392642/page-79#post-13625050

If you wish to ignore it entirely that's not my problem. I'm sick of your attempts at insults so it's best I just drop this conversation anyways. I don't see how "everyone" is going to miss that you've clearly ignored my translation and repeatedly act like it's incorrect or doesn't exist.

If you can point a single word or flaw in my translation, that at least shows that you even looked at it. The fact you can't even do that blows my mind, yet you still insist I'm incorrect, without even refuting it.

 

[graesand]

Yeah, that is my point (I graduated a ME 10 years ago, it's still fresh in my mind. This is sophomore level dynamics). 183nm is insignificant compared to what's out there. Without electronic aids, it's not farfetched for a low power car to snap into oversteer which a lot of people thing is foreign with production cars. 2nd gear, which people are experiencing is still near 300nm of torque!

Indeed sophomore dynamics, doesnt turn this problem more into a on off switch, as the oversteer feel in GT.

the torque curve, throttle response, friction curve, suspension travel, body rigidity all pretty much feel like an on off switch in GT.

Im not saying you are wrong, im saying the game feels wrong. Game bad.

Im having a hard time understanding the torque argument in the snap oversteer situation. Like does torque make a car snap oversteer? Might it not be a poor chassis that let it? Basically overloaded suspension that "pops"? Id use that for scandinavian flicks but wouldnt want to be in the passenger seat.

 

[driftnick13]

RX-Vision GT3 understeers trying to do hairpins at 40kph with a wheel, has no issues with the controller.

 

[graesand]

Im just really failing so hard right now at getting why i can run all other sims just fine, and drive a miata irl like i stole it. And i dont even have my degree yet.

 

[Firestone]

Indeed sophomore dynamics, doesnt turn this problem more into a on off switch, as the oversteer feel in GT.

the torque curve, throttle response, friction curve, suspension travel, body rigidity all pretty much feel like an on off switch in GT.

Im not saying you are wrong, im saying the game feels wrong. Game bad.

Im having a hard time understanding the torque argument in the snap oversteer situation. Like does torque make a car snap oversteer? Might it not be a poor chassis that let it?

I'm not quite sure what is there not to understand. People are getting caught out with oversteer with throttle application. Most people have never disabled all the aids on their car before the track it. Their cars are saving them most the time. Induced understeer from factory cars is much more the stability controls. The cars in GT were very slippery at the limit but still controllable, it's when you over apply throttle it tends to break.

This guy is driving his FRS without any aids. I set the time stamp before the right corner. He's driving very light. Notice how the car snaps and I do believe he is on R Compound tires. He's barely on the throttle. He's probably transmitting 25% the max torque. He is explaining throughout the video how careful he needs to be in throttle application.

This definitely aligns with the snappy feeling. I've been saying before, the cars in GT were driving raw simulating no aids.

 

[Firestone]

What I've translated is here https://www.gtplanet.net/forum/threads/gran-turismo-7-physics.392642/page-79#post-13625050

If you wish to ignore it entirely that's not my problem. I'm sick of your attempts at insults so it's best I just drop this conversation anyways. I don't see how "everyone" is going to miss that you've clearly ignored my translation and repeatedly act like it's incorrect or doesn't exist.

If you can point a single word or flaw in my translation, that at least shows that you even looked at it. The fact you can't even do that blows my mind, yet you still insist I'm incorrect, without even refuting it.

Ok, so he explained a minor thing that GT needs to do a little better with. You are over here dismissing the whole physics engine based on a small detail. His statements surround that is all positive.

Edit: the fact still remains that he's been overly positive of the simulation of wet weather and constantly states that it's the best he has ever driven in the game. He has multiple videos explaining the wet.

 

[wheelhp]

Ok, so he explained a minor thing that GT needs to do a little better with. You are over here dismissing the whole physics engine based on a small detail. His statements surround that is all positive.

One hell of an assumption to make about my position. One hell of a strawman. At least you can finally say my translation is INDEED CORRECT. jesus, thought you'd never even look at it!

 

[Firestone]

One hell of an assumption to make about my position. One hell of a strawman. At least you can finally say my translation is INDEED CORRECT. jesus, thought you'd never even look at it!

You are picking and choosing narrow statements and drawing a big conclusion surround it.

 

[wheelhp]

You are picking and choosing narrow statements and drawing a big conclusion surround it.

Where have I said my conclusion exactly? Only you have said what my conclusion is because it's you that's drawing my conclusion for me instead of understanding mine, as I have not said it yet.

 

[graesand]

Hes also explaining he removed the stock lsd and replaced it, how the oem brake assist, lsd brake assist are disconnected.

Look i see your point and i get it, but all i have for reference is driving a miata as a total asshole for some time and that did not want to kill me like GT. Maybe my wheel is wrong but then im really intrigued because it works for me in all other sims.

I havent got much bragging rights other than that miata when it comes to driving fr cars, used to torture a 320 w210, driven a sierra for a couple of years like i hated it, had a couple of slowish but well handling ff cars and had a couple of weeks go in a FF 420hp volvo. I would most certainly be dead by now if they handled like GT.

 

[graesand]

Oh and btw none of those calculations involve dynamics to my knowledge. Its all made up as a static problem. Whatever i dont know why im trying in this thread. People like the way a stock 200hp 1200kg car handles on comfort tyres in this game have at it. Im lucky i have my pc with vr in the winter and probably get to drive miata in the summer. Also gt sport maybe didnt suck that hard after some thought and as a pure gt title the 6 wasnt that bad and the 4 is still my legend. Good night

 

[extreme car]

He definitely snapped in the video

where? when he did a full lock and full throttle donut? all I'm seeing is understeer and power slides no snap oversteer to see.

I'm not quite sure what is there not to understand. People are getting caught out with oversteer with throttle application. Most people have never disabled all the aids on their car before the track it. Their cars are saving them most the time. Induced understeer from factory cars is much more the stability controls. The cars in GT were very slippery at the limit but still controllable, it's when you over apply throttle it tends to break.

This guy is driving his FRS without any aids. I set the time stamp before the right corner. He's driving very light. Notice how the car snaps and I do believe he is on R Compound tires. He's barely on the throttle. He's probably transmitting 25% the max torque. He is explaining throughout the video how careful he needs to be in throttle application.

This definitely aligns with the snappy feeling. I've been saying before, the cars in GT were driving raw simulating no aids.

you didn't set the time stamp on the video. Automatic 86 came with open LSD as standard here in Australia, it'll be pretty hard to slide that car unless you flick it or pull the hand brake.

 

[graesand]

Arguably the top five threads in the gt 7 forum right now are about how bad the game is for some reason or another, look at their IG page and its even worse, and the comments about physics are many there too.

Im hoping PD comes forward with some sort of public acknowledgement of the apparent flaws. Just turning the game on its apparent its broken when youre met with music rally and a really nonexhaustive list of the many problems the dev seem to have snapped up and are glancing over. Id rather they come forward day one and say hey guys, just pd stuff going on here, game is unfinished so you dont get to play more than a restricted part til we have done beta testing. Because really, can you even compare this gt in its current state to the standard that gt5/6 held when it came out. Its a freaking beta of gtsport 2.0