Balancing Differing Cars in Mod

[RotaryRacer787b]

Yet another GTR2 question from me. I’m using multiple mods to create a single car set, and trying to find the best way to adjust some of the cars to race each other.

For example, a Ford GT40 and Ferrari 330 are well balanced when braking and cornering. However an Alpine A220 will brake significantly later and almost be flat out through the corners and able to overtake any other class of cars. I would like to be able to adjust the Alpine to behave more realistically.

Outside of some of the suspension tweaks in Von Dutch’ tutorial, and increasing weight to an unrealistic level, is there some component of the car I need to look at? Maybe the tire file?

 

[jgf]

The Alpine handles well in turns because of relatively low power, it should be at a distinct disadvantage on straights. That said, you can try tweaking tire grip, but - make a copy of the particular tyr file, rename it, and put that in the Alpine folder then edit it (change grip settings slightly), otherwise you will affect all cars using that tire. You can tweak the brake settings in the hdc file (I believe torque is the one), but again, this will affect anyone, you or the AI, when driving this car.

Or, what I would try first, edit the talent files for that car, lowering the cornering abilities; if there are no talent files, create them (Tom's Talent Scout and Tom's Driver Shop simplify this); and make sure there are no multiple talent files for any driver (file name doesn't matter, GTR2 looks at the name on the first line of the file). FWIW, talent files are a pain because the game will read them anywhere, all the separate folders are just for the convenience of us mortals; so if you want separate stats for the same driver in different series you'll have to be inventive with names - Mario Andretti, M Andretti, M. Andretti, Ma Andretti, etc., even Andretti_F1, Andretti_Indy (I've downloaded series with Driver 1, Driver 2, etc.)

 

[Speednut357]

I think it would be easier to start with Talent files, It would be possible to adjust certain aspects of the car, like the engine's power, the tires' grip, and the brakes' strength. However, making these changes can be quite complex.

for example

In the tire file, there is a table of numbers called the "tire slip curve". This chart shows how the tire behaves when it slips at different speeds and angles. This is important to understand, but not what we want to change.

Instead, we want to focus on the sections of the tire file that define the different types of tires, such as soft, medium, and hard. At the beginning of each of these sections, there is a line that says "Drylatlong" followed by two numbers in parentheses.

These numbers represent the tire's grip on a dry track surface. By adjusting these numbers, we can increase or decrease the amount of grip that the tire provides. This, in turn, affects how the car behaves on the track. For example, increasing the grip value will make the car easier to handle, while decreasing it will make the car more difficult to control.

The first number represents the lateral grip coefficient of the tire, which is the tire's ability to provide grip during cornering or turning. This number is typically higher than the longitudinal grip coefficient, as cornering requires more lateral force.

The second number represents the longitudinal grip coefficient of the tire, which is the tire's ability to provide grip during acceleration or braking. This number is typically lower than the lateral grip coefficient, as the tire needs to transfer weight to the front or back of the car during acceleration and braking.

This will not specifically slow the Ai down in the corners but rather change the way the Ai behaves during the corner as it adjusts speed for the available grip level. and adjusting these numbers by very small amounts will make a noticeable difference. I normally adjust by 0.1 and test.

Next would be the brake power adjustment.

In the RCD file, the term BrakePressureSetting refers to the pressure setting of the car's brake system. The number that follows represents the maximum amount of pressure that can be applied to the brakes.
A higher number for the BrakePressureSetting means that the brakes can handle more pressure and, therefore, can provide more stopping power. However, too much pressure can cause the brakes to lock up and the wheels to stop rotating, which can make the car spin out of control. So, the BrakePressureSetting needs to be carefully adjusted to find the optimal balance between stopping power and control. It is important to note that the Ai will brake earlier if there is less power available. Again small changes.


These are just a couple of things you could possibly change. There are many more. Maybe jgf will have a more simple approach, I tend to overcomplicate things.

 

[jgf]

Never edit the car physics based on how the AI drive, they are imbeciles. How does the Alpine perform when you drive it? If it is acceptable then it is definitely an AI issue; if there are no talent files for a car it falls back on hard-coded stats and will usually be too fast and too aggressive (many mods have no talent files, or merely used default settings for all). The talent files cannot make a car "faster" only control aggression and ability in slow and fast corners, these are the pertinent lines:

// Increase attempted low-speed cornering by adding a minimum onto calculated speed.
// Reduce attempted high-speed cornering by multiplying speed by a number less than 1.0.
// <adjusted speed> = CorneringAdd + (CorneringMult * <original speed>)
CorneringAdd = 5.885 // Higher number increases low speed cornering
CorneringMult = 1.064 // Higher number increases high speed cornering

Set these too high and the AI will spin out as their attempted speed exceeds grip, set too low and they become roadblocks.

 

[Speednut357]

Always change physics son. And stop being such a grumpy old man. This is a discussion not a measure of your manhood.

 

[jgf]

I said never change the physics based on how the AI perform in the car.

But to make you happy this grumpy old man will shut up and just lurk from now on.

 

[Jempy]

We must not forget that "realistically" ( as said in 1st post ) this Alpine A220 was first of all created for Le Mans.
But, finally, this car was surely perfectly quick in corners but too slow in the long straights of the track in those years. ( +- 20km/h slower for the Alpine compared to the Ford for example )

 

[RotaryRacer787b]

I appreciate all of the feedback! I went through and found that it was not an AI issue in this instance, but the way the differing mod creators chose to balance the grip of their respective cars.

Taking the advice of JGF, I went on a test and found that even as I drove it, the grip was insane. Even to compare to cars in its class, I could barely brake at all in a large majority of corners. I then found that the tire file was the culprit.

While in the original PnG cars I was using as the base, most cars had a grip of say 1.365 for the lat grip, the Alpine (and a couple of others) were more in the 2.100 range. Adjusting this tire file was all that was needed to get the cars in line.