Gran Turismo 7 Physics

[ScottPuss20]

Oh, front ride height you say? Here you go.

Daily race 500PP. This is just ridiculous. This lowers the PP value allowing one to upgrade power of the car making it much faster than normally. Tried it for myself, and ironically it reduced lateral weight transfer making car handle better and more stable ... Physics don't exist in this game.

I just remembered that this was also an issue in GT5...

 

[GTboyz]

Oh, front ride height you say? Here you go.

Daily race 500PP. This is just ridiculous. This lowers the PP value allowing one to upgrade power of the car making it much faster than normally. Tried it for myself, and ironically it reduced lateral weight transfer making car handle better and more stable ... Physics don't exist in this game.

Yeah I tried it for the GT40 and it handles a lot better than stock LOL

 

[danardif1]

This is a setup for the Audi that uses the suspension settings from my Coach Dave race setup for the same car, translated into the Natural Frequency figures. Ride height is the same, toe figures are the same, camber is different because of the differences between the game, but I've tried to match as much as possible, and it works!

Front springs in nm are 174000
Rear springs in nm are 173000

See the difference once the weight over the axle and then converting that into hz makes...

 

[Galvston]

View attachment 1172011

This is a setup for the Audi that uses the suspension settings from my Coach Dave race setup for the same car, translated into the Natural Frequency figures. Ride height is the same, toe figures are the same, camber is different because of the differences between the game, but I've tried to match as much as possible, and it works!

Front springs in nm are 174000
Rear springs in nm are 173000

See the difference once the weight over the axle and then converting that into hz makes...

is this plug n play? Or do I have to convert some figures still? I'm sorry I didn't understand your last sentences

 

[danardif1]

is this plug n play? Or do I have to convert some figures still? I'm sorry I didn't understand your last sentences

The setup on the screen is plug and play. The Hz figures for the suspension have been converted from ACC's newton meters to GT's Natural Frequency Hertz.

Realistic suspension settings from well-regarded sims seem to work quite well in GT7. There are still flaws and issues but this is just highlighting one aspect where GT is actually simulating to what I think is a high level.

 

[Galvston]

The setup on the screen is plug and play. The Hz figures for the suspension have been converted from ACC's newton meters to GT's Natural Frequency Hertz.

Realistic suspension settings from well-regarded sims seem to work quite well in GT7. There are still flaws and issues but this is just highlighting one aspect where GT is actually simulating to what I think is a high level.

Tried your settings. Fantastic I must say. It was so different and better than stock suspension, that I searched for more from Coach Dave but unfortunately it's paid right?

It felt much more similar to ACC, and I feel like the sudden grip loss that some people complain about with the R8 was cured, and was more progressive. In my opinion it felt much more realistic, more people should try this...

 

[Bullwinkle]

View attachment 1172011

This is a setup for the Audi that uses the suspension settings from my Coach Dave race setup for the same car, translated into the Natural Frequency figures. Ride height is the same, toe figures are the same, camber is different because of the differences between the game, but I've tried to match as much as possible, and it works!

Front springs in nm are 174000
Rear springs in nm are 173000

See the difference once the weight over the axle and then converting that into hz makes...

This is promising! Thank you!

Can you explain your conversion procedure again, step by step? I’m still confused about the steps that I’d take to calculate the natural frequency based on axle weight. I’d love to run some numbers and experiment. Perhaps you can use this car as an example, from beginning to end, so we can all try it out?

Very much appreciated!

[edit] I forgot to clarify, is there a way to calculate this without the Coach Dave settings?

 

[danardif1]

This is promising! Thank you!

Can you explain your conversion procedure again, step by step? I’m still confused about the steps that I’d take to calculate the natural frequency based on axle weight. I’d love to run some numbers and experiment. Perhaps you can use this car as an example, from beginning to end, so we can all try it out?

Very much appreciated!

[edit] I forgot to clarify, is there a way to calculate this without the Coach Dave settings?

Okay so to clarify this is not a method of necessarily building a setup yourself, it is a way of using information from other sources whether it's real world data or setup information from other sims and converting them for use in GT7.

So my source in this case is the paywalled Coach Dave database for ACC, but you can use user-generated setups from these other games that you find online, youtube etc. Even the presets in ACC would probably be useful themselves as the Aggressive Preset for most cars is very useable.

I will use the spring rate settings for the Coach Dave race setup for the Audi at Laguna Seca as an example.

In ACC the Coach Dave spring rates are;

Front - 174000 nm

Rear - 173000nm

Now we need to find a way to convert it into Natural Frequency.

First step will be to work out what the mass of the car is over each axle, as this will dictate the frequency of the spring when combined with the spring rates.

The Audi weighs 1235kg with a weight distribution of 42-58 (that rearward bias is why so many are having trouble with this car if it's not set up right)
Using these figures we can work out that the weight on the two front wheels is 259.35kg each, and 358.15kg on each rear wheel. I used the percentage calculator page for this, but if you're suitably mathematically inclined you could work it out yourself I suppose (I am not blessed in this regard).

This is then where we need to use the spring frequency calculator page I linked. On this page it will ask for the Spring Constant, this is our nm figure that we've sourced from Coach Dave or elsewhere, then the mass, which is the weight on one particular wheel. Click calculate and you get the resulting hz figures.

Front
Spring Constant - 174000nm
Mass - 259.35kg
Natural Frequency - 4.122 (rounded down to 4.12 for GT)

Rear
Spring Constant - 173000nm
Mass - 358.15kg
Natural Frequency - 3.498hz (rounded up to 3.50 in GT)

Now this method could still be useful even if you don't have a source for nm spring rate settings for a car (for example the fictional Gr3 cars in the game), because with enough research into equivalent spring rates for other cars of it's type you could make approximations of what they could be and use them as a basis to generate a realistic natural frequency figure. I've tried this with the Jaguar and whilst I haven't found the sweet spot yet I have made progress.

 

[danardif1]

Tried your settings. Fantastic I must say. It was so different and better than stock suspension, that I searched for more from Coach Dave but unfortunately it's paid right?

It felt much more similar to ACC, and I feel like the sudden grip loss that some people complain about with the R8 was cured, and was more progressive. In my opinion it felt much more realistic, more people should try this...

I spent last night going through all my Coach Dave setups for the tracks that are in both games and having an equivalent setup in GT7 for the car. I even tried for the Laguna Seca one the same exact camber settings, and it does feel very much like the car does in ACC...

GT7 certainly has flaws, but it's definitely a simulation in my eyes. Realistic setups from ACC produce very similar results in GT7, even to my surprise! I was chuckling whilst lapping Laguna Seca last night because it was so similar to the ACC version...

If you're looking for more like this but obviously don't want to pay for Coach Dave because they're not strictly setups for GT... just go to youtube, there are lots of very good setups for ACC that would still be useful in GT7 given how similarly they seem to perform.

 

[Mr616]

@danardif1 Thank you for your insight and sharing this info. If I could double like, I would

That's an evening of testing sorted for me.

 

[F30clubman]

View attachment 1172011

This is a setup for the Audi that uses the suspension settings from my Coach Dave race setup for the same car, translated into the Natural Frequency figures. Ride height is the same, toe figures are the same, camber is different because of the differences between the game, but I've tried to match as much as possible, and it works!

Front springs in nm are 174000
Rear springs in nm are 173000

See the difference once the weight over the axle and then converting that into hz makes...

I made these settings on the '15 Audi GT3. It drives great. Thanks a lot!

Understandable that PD leaves the challenge up to us to find good suspension settings. But from the other side I can not understand that PD does not allow suspension and differential settings in online races with BoP. Why do they make it mandatory to race with GT3 cars with an unusable set-up?

 

[Galvston]

I made these settings on the '15 Audi GT3. It drives great. Thanks a lot!

Understandable that PD leaves the challenge up to us to find good suspension settings. But from the other side I can not understand that PD does not allow suspension and differential settings in online races with BoP. Why do they make it mandatory to race with GT3 cars with an unusable set-up?

Exactly. Dumb decision. Car drives much better not stock

 

[danardif1]

Exactly. Dumb decision. Car drives much better not stock

There is the option to have open setups with BOP applied but at the moment unlike Sport where your already saved setups are selectable, if I join a lobby with BOP and open setups now it will apply the BOP and then reset the setup meaning I'd have to put it back in manually...

This is just silly. The point of having the option of BOP plus setups is that you can come in with the setup you've worked hard on and use it. That's how our league racing works on Sport and is what would stop us from moving onto 7...

 

[danardif1]

One other point as BOP has been brought up...

Remember that if the BOP for your car involves adding weight, your suspension calculations need to take that into account as now the mass over each axle will be slightly different, so it may be worth having duplicates of each setup you make for non-BOP and BOP scenarios.

I think the Audi in BOP trim is 1260kg instead of the 1235kg base weight, but I think also the weight is applied in the middle of the car so the distribution should remain the same, it's just the actual weight over the axles that will be slightly different.

 

[Bullwinkle]

Understandable that PD leaves the challenge up to us to find good suspension settings. But from the other side I can not understand that PD does not allow suspension and differential settings in online races with BoP. Why do they make it mandatory to race with GT3 cars with an unusable set-up?

It's because they tied suspension settings with the PP values. In a BoP race any change in suspension will change the BoP. As we saw the last couple of weeks with open tuning races in Sport Mode, this is a stupid decision on their part. I hope they decouple the suspension the same way they did the transmission once they discovered the Tomahawk glitch. If they'd do this one simple thing, all tuning races would be much more interesting (at least I think they would) and challenging. Meta cars would become less relevant as people would be able to adjust suspension settings to match their driving preferences. It would make even a one-make race tons more interesting! I'm hoping they just admit this and give in soon.

 

[danardif1]

It's because they tied suspension settings with the PP values. In a BoP race any change in suspension will change the BoP. As we saw the last couple of weeks with open tuning races in Sport Mode, this is a stupid decision on their part. I hope they decouple the suspension the same way they did the transmission once they discovered the Tomahawk glitch. If they'd do this one simple thing, all tuning races would be much more interesting (at least I think they would) and challenging. Meta cars would become less relevant as people would be able to adjust suspension settings to match their driving preferences. It would make even a one-make race tons more interesting! I'm hoping they just admit this and give in soon.

It's an odd choice in relation to the more fixed categories like Gr3 etc as surely the fact there's a BOP system for power and weight within these categories negates the need for PP to be relevant at all?

The fixed setup Daily Races that are Gr3 I tend to just stick to cars that I like the fixed setup on, I don't go for this hopping around between cars to find the 'Meta' car as it were. If it means I'm less competitive so be it really...

 

[Bullwinkle]

It's an odd choice in relation to the more fixed categories like Gr3 etc as surely the fact there's a BOP system for power and weight within these categories negates the need for PP to be relevant at all?

The fixed setup Daily Races that are Gr3 I tend to just stick to cars that I like the fixed setup on, I don't go for this hopping around between cars to find the 'Meta' car as it were. If it means I'm less competitive so be it really...

My sentiment as well. It should be balance of power, not balance of simulated performance points. Just assign every car the same weight-to-power ratio, and let us fiddle with the rest to suit our tastes. Seems obvious and exceedingly simple. . .

 

[Mr616]

View attachment 1172011

This is a setup for the Audi that uses the suspension settings from my Coach Dave race setup for the same car, translated into the Natural Frequency figures. Ride height is the same, toe figures are the same, camber is different because of the differences between the game, but I've tried to match as much as possible, and it works!

Front springs in nm are 174000
Rear springs in nm are 173000

See the difference once the weight over the axle and then converting that into hz makes...

Tried this tune tonight. Huge improvement over stock. A lot less floaty feel and very stable. It's a bit to "tight" for me so i'm trying some slight tweaks but these spring settings seem to give the car great balance and a great base to tune off.

I'm using Sardegna 800pp race as my test. The R8 is running 750ish pp on racing medium tyres. I'm also back to standard gearbox just for consistency. I'm only changing suspension and diff settings one bit at a time back to backing. Fastest laps are curently mid 1.38s

 

[BigSarj]

So what does this mean? It's a very cool discovery, to be sure, but what does it say about the devs' abilities to set up a good car? Especially when in the context of BoP.

 

[danardif1]

So what does this mean? It's a very cool discovery, to be sure, but what does it say about the devs' abilities to set up a good car? Especially when in the context of BoP.

That has to be considered in the context that PD are releasing games that are played by people of wildly different abilities on a range of different input devices. That the default setups are poor in the eyes of a more serious sim racer needs to balanced against that person who is far more green to this stuff and is just enjoying chucking a cool looking racing car round a track without much regard to the more detailed stuff.

That being said the default for the Audi in particular is awful. If PD were as serious I think about the esports angle regarding BOP as Kunos and SRO are with ACC they should invest time in getting these cars more sorted. Especially as there is something good in their simulation I think.

The key for me is that realistic setups produce realistic results in this game and there is a relatively easy way to make them behave as such.

 

[Mathaios_C]

Nust bought the thurstmaster t300 rs gt. Which setting are you guys using? I read sooo many different opinions about it.

 

[Iso Octane]

Thanks for pointing us in this direction danardi.

I'm curious about road cars and have only had a chance to try it with the GR86. Frustratingly it doesn't allow me to set a low enough number on the rear... nevertheless... with only the adjustment to the suspension frequency to try and match real life, it's so so so much better when it comes to oversteer characteristics.

Can't wait to try some other road cars especially those that Assetto Corsa has.

Also curious to know if GT7 has consistently wrong suspension values for road cars. And if so, why so lazy PD?

 

[ScottPuss20]

That being said the default for the Audi in particular is awful.

Yes it is. That's the problem which prevents me from driving it consistently.

 

[Bullwinkle]

@danardif1 The thing that surprises me about the R8 tune is that the rear springs are so soft while also bearing a majority of the weight. This is the opposite of what I expected. Is it because it’s an MR drivetrain? Do you have a tune for a RR car for comparison?

 

[DivitLad]

Nust bought the thurstmaster t300 rs gt. Which setting are you guys using? I read sooo many different opinions about it.

I use 2 or 3 torque and 7 or 8 sensitivity depending on the cars n tracks I'm driving

 

[Mr616]

Thanks for pointing us in this direction danardi.

I'm curious about road cars and have only had a chance to try it with the GR86. Frustratingly it doesn't allow me to set a low enough number on the rear... nevertheless... with only the adjustment to the suspension frequency to try and match real life, it's so so so much better when it comes to oversteer characteristics.

Can't wait to try some other road cars especially those that Assetto Corsa has.

Also curious to know if GT7 has consistently wrong suspension values for road cars. And if so, why so lazy PD?

I've only done limited testing to the R8 Evo really, but I did notice you cannot apply this to the Huayra. The values aren't high enough. Danardif1 did mention it may only be applicable for race cars.

I do think the spring rate/frequency could be the single most important setup, followed by diff. You can chase your tail with finding setup, but have a base to work from, and credible info to help can make tuning way more straight forward.

I will continue to try this on the Lambo, 458 and Porsche GR3s and see what happens. I was tuning out the horrible standard tunes with diff and flattening the ride height (sometimes ballast) but correct spring settings would seem to negate the need for ballast which I like.

On the subject of BOP. They need fixed or limited ride height (or fix the bug), with bopped power and weight and leave setup to the individual. So many cars are hamstrung by awful defaults.

 

[danardif1]

@danardif1 The thing that surprises me about the R8 tune is that the rear springs are so soft while also bearing a majority of the weight. This is the opposite of what I expected. Is it because it’s an MR drivetrain? Do you have a tune for a RR car for comparison?

This is the trap many have fallen into because of how these figures work. Look at the spring rates I used to reach those NF figures. It's precisely because of the weight at the rear that the NF is lower despite the spring rates being comparable to the front. The NF figure being lower does not necessarily mean the springs are softer....

This is the reason that weight distribution being a visible part of GT7's setup options was so important for finding this out.

If GT7 had the 911 GT3 car rather than the RSR GTE I could use the Coach Dave setups for the ACC Porsche as an example of this too, as yes the spring rates do tend to be higher for the rear on RR cars.

 

[danardif1]

I've only done limited testing to the R8 Evo really, but I did notice you cannot apply this to the Huayra. The values aren't high enough. Danardif1 did mention it may only be applicable for race cars.

I do think the spring rate/frequency could be the single most important setup, followed by diff. You can chase your tail with finding setup, but have a base to work from, and credible info to help can make tuning way more straight forward.

I will continue to try this on the Lambo, 458 and Porsche GR3s and see what happens. I was tuning out the horrible standard tunes with diff and flattening the ride height (sometimes ballast) but correct spring settings would seem to negate the need for ballast which I like.

On the subject of BOP. They need fixed or limited ride height (or fix the bug), with bopped power and weight and leave setup to the individual. So many cars are hamstrung by awful defaults.

From doing this work I have found that yes the Natural Frequency is almost the central point of setting up the car. Get those in a good window that balances out the car and you're a decent way along to getting the rest right too.

From my perspective of league racing weekly on ACC, currently 6 weeks into racing the Audi funnily enough... In practice and testing the tweaks that I go for if there's something I perceive to be a handling imbalance are roll bars and ride height. These also seem important in GT7 to achieving a good setup BUT they seem to be in a far narrower operating window than my ACC experience. In all the running I've done with the Audi with my 'translated' setups, I have not been able to replicate the ride heights I use on ACC because they make the rear way too loose. The car has to be run as low as possible. Now I'm only talking a difference of a few millimetres even on ACC, but on GT7 I have found the car becomes too nervous at anything above 62mm at the rear, when conversely I might be running at 65mm at the same circuit in ACC with a stable rear end and good traction.

EDIT - Funnily enough you mention the values on some cars not being high enough to replicate the approach on... I was looking at the CD setups for the AMG GT3, and some of the race setups on there have rear spring rates that once converted into Hz are too low for the available range on GT7...

 

[danardif1]

@Bullwinkle there is a car I could try and put a setup together for that's rear-engined... The modern Alpine A110. There is a GT4 version in ACC that the equivalent tune-able version we have in GT7 shouldn't be too far of for a RR comparison...

I'll see what I can do with it.

 

[Bullwinkle]

@Bullwinkle there is a car I could try and put a setup together for that's rear-engined... The modern Alpine A110. There is a GT4 version in ACC that the equivalent tune-able version we have in GT7 shouldn't be too far of for a RR comparison...

I'll see what I can do with it.

Did I say rear? I meant front. The Audi is an MR, which accounts for the different weight balance. I’m curious what spring settings look like for a heavy front end so I can fiddle with things.

This could potentially be a really big deal for tuning…