GTR2 tyre slip curve and grip

I recall an old tyre mod back in 2006 : New Advanced Physics Patch (NAPP mod) with a slightly different feel from vanilla.
A little late, but this?

"What’s new in V 1.4 (28/12/2006)
- Some minor fix to adapt the NAP to the GTR2 1.1 official patch
- Added functional motec cockpit displays (brake temps, tyre temps, water,
oil and time gaps) for Ferrari 360, Ferrari 575, Maserati MC12 and
Gillete Vertigo

What’s new in V 1.3 (05/11/2006)
- Soft tyres are reaching optimum temperature a bit more easier. They should be
able to work well even with the lowest ambient and track temperatures.
- All wet and intermediate tyres have new grip curves that gives them better
control and a bit more grip.
- All wet and intermediate tyres gain temperature harder than before.
- All wet and intermediate tyres have more grip when cold.
- All wet and intermediate tyres are more grip sensible with pressure.

What’s new in V 1.2 (29/10/2006)
- Safety car that doesn’t apper on dedicate server fixed
- Fixed a tyre temperatures bug on Yokohama tyres
- Added the option to lower down the POV to see the motec on 16:9 monitors and
to have a more realistic view
- Engines modified for leagues that wish to use Timed Scaled Damage option.
admins for additional information. "

I never tried this, at the time it was rather controversial, but will upload if anyone is interested.
 
Yes you can, it is available in hq anniv. patch but it would be interesting to have it for people who prefer stock experience...well if they add NAP it is no more stock GTR2... which breaks rule #1 of stock game players :D

The main problem with stock physics is the excessive amount of tyre grip...but from my experience it is been done like that to help AI (maybe to help arcade players to like gtr2 too...) which tends to slip for any reason especially on wet : you do not really notice that on stock tracks but once you try any modded track it could be total AI carnage :D
 
The main problem with stock physics is the excessive amount of tyre grip...but from my experience it is been done like that to help AI (maybe to help arcade players to like gtr2 too...) which tends to slip for any reason especially on wet

And that has been the myth since the beggining. It is true that there is too much tyre grip BUT only for medium and hard slicks tires. Soft slicks however are spot on. What is the main problem with original physics is too much aerodynamic downforce and too small drive-train loss simulation. The reason AI slips so much is because of too high peak slip values inside tyre files for the AI cars. AI then steers too much into a corner and loses grip. All of this has been addressed in my GET REAL mod and finally fixed.
 
I dig up an old video but an interesting one about the different kinds of GTR2 tyres. In this video Man Hobby explains the differences between 3 tyre manufacturers (Michelin, Pirelli, Dunlop) :

That same video is also referenced in my documentation which describes changes I have made to the physics in great detail. One can immediately observe how different Pirelli tires curve is compared to other two. This leads me to believe that this is actually longitudinal slip curve for the acceleration based on my research and not lateral. It would be great if someone could upload that program which shows the graphs like listed above. My mod models all three slip curves separately for lateral slip, braking and acceleration unlike original physics.

As for the NAP mod it is a fantasy. Its harder to drive yes, but not more realistic by a long shot. I will post just 3 examples:

- tyre slip curves are fictional with double peak (GTR2 uses real lateral curves!)
- body drag values are fictional (as is other stuff)
- they reduced downforce by a half so cars have less downforce and by that logic they are more realistic!
:)
 
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@Need_For_Speed,

I am curious - as part of your effort, did you look into wet tires/rain racing? What are your thoughts on it? Do stock GTR2 cars behave as they should according to the physics, and if not, is there a potential for improvement via car/tire adjustments, or is rain just too simple in GTR2?

Thank you and good luck with your effort :)
 
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@Need_For_Speed,

I am curious - as part of your effort, did you look into wet tires/rain racing? What are your thoughts on it? Do stock GTR2 cars behave as they should according to the physics, and if not, is there a potential for improvement via car/tire adjustments, or is rain just too simple in GTR2?

Thank you and good luck with your effort :)
They are using identical curves as slick tires which almost certainly isnt right. There are differences other than grip levels between them though if you look into the files.
Cars behavior in wet conditions looks convincing to me.
 
Yes you can, it is available in hq anniv. patch but it would be interesting to have it for people who prefer stock experience...well if they add NAP it is no more stock GTR2... which breaks rule #1 of stock game players :D

The main problem with stock physics is the excessive amount of tyre grip...but from my experience it is been done like that to help AI (maybe to help arcade players to like gtr2 too...) which tends to slip for any reason especially on wet : you do not really notice that on stock tracks but once you try any modded track it could be total AI carnage :D
Many sims over the years have fudged things for "gameplay". Even the venerable GPL had some tracks (notably Nurburgring) widened for "better racing". I recall the original GTR was like hard slicks on ice, then I got GTR2 and it seemed they'd gone too far in the other direction, I was now driving slot cars.

The NAP mod was controversial for the same reasons; one group saying "this is wonderful! much more realistic, this is what GTR2 should have been", the other group saying "this is too much like the original GTR, too little grip, weird handling". I'll upload it, may be useful for someone, or may just be good for a laugh today (much like me).
 
What I appreciate about NAP though, they at least explained what they tried to do (although argument of "how come professional driver struggles, but gamer handles with ease" is not exactly scientific :)) But they tried to fix, for example CoG and IIRC fuel tank location. I am excited to see that something more deeply researched is available.

Need For Speed - I appreciate your response, but could you clarify - is rain racing in scope for your effort, or not?
 
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@Need_For_Speed,

I am curious - as part of your effort, did you look into wet tires/rain racing? What are your thoughts on it? Do stock GTR2 cars behave as they should according to the physics, and if not, is there a potential for improvement via car/tire adjustments, or is rain just too simple in GTR2?

Thank you and good luck with your effort :)
I can't vouch for default values but be very wary of tires in mods, people edit those to whatever they like with no regard to realism. I recently tweaked a mod that only had soft slicks ...and the wet grip was better than the dry.

As for rain, the best I can tell the effect is modeled as a proportional lowering of grip with the severity of rain, with a gradual increase with the start of rain and a more gradual decrease after it stops. Ambient temperature seems to have an effect also, somewhat tempering the loss of grip and the track drying more quickly on a hot day, though I cannot quantify this (it may be all in my head ...plenty of room for it).
 
As for rain, the best I can tell the effect is modeled as a proportional lowering of grip with the severity of rain, with a gradual increase with the start of rain and a more gradual decrease after it stops. Ambient temperature seems to have an effect also, somewhat tempering the loss of grip and the track drying more quickly on a hot day, though I cannot quantify this (it may be all in my head ...plenty of room for it).
I agree, my observation too :) But did not realize the ambient temp impacting stuff. Overall, that's why I said "rain model too simple". And yeah, plenty of quick converts from rF1 with no rain tires, at all :(
 
They are using identical curves as slick tires which almost certainly isnt right. There are differences other than grip levels between them though if you look into the files.
Cars behavior in wet conditions looks convincing to me.
Definitely. Hard tires, rain tires, and treaded tires have much greater deviation than soft slicks. But how much, and under what conditions? Hard data is nearly impossible to find; tire manufacturers guard this as strongly as state secrets. Even race sim devs are reticent to divulge where they got tire data ..."from teams".
 

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