Assetto Corsa PC Mods General DiscussionPC 

  • Thread starter daan
  • 139,170 comments
  • 38,250,242 views
Hello, I already introduced myself. I'm the author to a physics mod for Kunos' Supra, and any others who would wish to use it if they ask me. I'm here because I was informed someone ripped my work without permission, and I read some misconceptions here so I decided to clear them up.

I don't think you understand. The mod on page 476 is *already* using my physics. The developers also alter the .ini files in the data folder: I don't get your point.

The data comes from:

Laserscan from Aad Hofman
Toyota manuals
Toyota PR publications
HKS
Best Motoring
And some stuff from forums.

I was generally lucky with this car and most of the data is reputable sources. All I really found from forums was some links to papers explaining the turbocharger and front lip operation and such things.

Leftover generics, stuff like:

[AUTO_SHIFTER]
UP=6800
DOWN=3500
SLIP_THRESHOLD=0.95
GAS_CUTOFF_TIME=0.300

and some values in the tires and drivetrain which are alright. I change load sensitivity, slip dropoff, camber sens, relaxation length, sometimes stiffness but most other minor things for which no one has any data for anyway are considered to be okay and can be left in as-is. Suspension is 100% by me, aero is 100% by me etc.

The Esprit Supra, I'm told, is largely using Kunos suspension: which we have collectively figured out to simply be *very* inaccurate. You know, via laserscanning and referencing to Toyota manuals to make sure it really does line up in the implementation. So in that way, it would make sense to use a properly implemented geometry.

Saw the update 1.3 on RD and I noticed you are still looking for more data on the ARB, hopefully this ARB test data that I got a few years ago might be of some use.
 

Attachments

  • SupraARBtest.pdf
    7.9 KB · Views: 39
Saw the update 1.3 on RD and I noticed you are still looking for more data on the ARB, hopefully this ARB test data that I got a few years ago might be of some use.
Very cool! Where is this from?

I just took a look but it looks sensible. I haven't yet verified it, nor can I really do it accurately because I'm still waiting on more precise dimensions, but I will definitely run the numbers on these and see if it's applicable to wheelrates or for calculations. You see, one large issue with ARBs on roadcars is that they're not directly bolted on metal-to-metal, so very likely your actual rates in the first few degrees aren't 1:1, so even with the most precise measurements and mathematics, if you ignore bushings and anything else worth note in the linkages...

EDIT: Simply applying approx. MR to endlink rates comes up with...really quite sensible wheelrates. Were these by any chance measured directly with the rubber bushings taken into account? :embarrassed:

Of course, extremely high chance for coincidence after just a few simple calculations.
 
Last edited:
I bought this Alfa Romeo 4C.....Italian modder.........skin looks messed up because he modified it like those URD/RSS/VRC ....

Sorry you have been had. For Italian modder read scam artist. The skin is not modified, the model is just really bad. Can't make a template without remapping the model.

Don't buy Assetto Mods. Except from URD, RSS, VRC, F3Classics. Other can pitch in here as I can't remember a few.
 
So myself, Ted and Kondor have driven many various types of race cars.

Myself - some open wheel stuff, closed body Grand Nationals, 125cc 6 speed shifter karts and 250cc SuperKarts were we raced as a support class with CART/ChampCar/Indycar on race weekends to name some.

I really get a good laugh at a few that honestly think that those that actually drive racecars (myself since I was 6 years old) for a living and then for fun, are told by a keyboard warrior how race cars work and how to drive them and what they're probably or "perhaps" doing wrong. All the while never admitting when they're known to be wrong and to have never even sat in a car.

This isn't an all high n mighty thing but if all you know are numbers, well..... that's all you know.
Cheers
 
Last edited:
Alright, if you're going to be cheeky about it and operate under the assumption that I don't know anything what I'm talking about, how about we forget me for a moment and quote Ross Bentley? Surely he has enough track experience and his authority should convince you. ;)


Ultimate Speed Secrets, mine is a hardcopy but I assume all are identical, Page 216 under Section 30 "Managing Errors." I found some Google Previews, but sadly page 216 is omitted, so you'll have to take my word for this one. Or just open your own copy. It's the text in the top left.

"ILLUSTRATION 30-5 A common error that many drivers make is "crabbing" into the corner, easing the car away from the edge of the track prior to turning in. That's cheating, and it's going to cost you. Be aware if your car is right against the track edge at your turn-in point."

This is what I thought of when I saw that section which I commented on. Later I started a conversation with the assumption "Perhaps it was intentional?".

More of a real-life example: but what if the outside is dusty or filled with water? ;)
You can't learn to drive from a book, dude. It's like trying to learn tennis from a book. Or guitar. Or f'ing ;)

Anyway, consider taking my advice. Anyone can try autocross (that's how I got started).

Here's a formula for you: Driving/Sim-driving = Sex/Porn ;)
 
You can't learn to drive from a book, dude. Anyway, consider taking my advice. Anyone can try autocross (that's how I got started).

Here's a formula for you: Driving/Sim-driving = Sex/Porn ;)
I'm sorry; but this is Ross Bentley's book!

While you're essentially correct in the sense that, no, the book won't *teach* you how to drive without actually practicing it yourself, you're essentially dodging the subject and it really looks like you're implying Ross' thoughts don't matter just because he wrote it down. :lol:

Okay, whatever. I could probably be directly copying sentences that instructors have told me, or directly from the book, or directly from instructional footage and I would still be wrong.
 
Very cool! Where is this from?

I just took a look but it looks sensible. I haven't yet verified it, nor can I really do it accurately because I'm still waiting on more precise dimensions, but I will definitely run the numbers on these and see if it's applicable to wheelrates or for calculations. You see, one large issue with ARBs on roadcars is that they're not directly bolted on metal-to-metal, so very likely your actual rates in the first few degrees aren't 1:1, so even with the most precise measurements and mathematics, if you ignore bushings and anything else worth note in the linkages...

EDIT: Simply applying approx. MR to endlink rates comes up with...really quite sensible wheelrates. Were these by any chance measured directly with the rubber bushings taken into account? :embarrassed:

Of course, extremely high chance for coincidence after just a few simple calculations.

I got the pdf from automotive forum long time ago, it was referenced in a Supra owner forum https://www.supraforums.com/threads/want-to-borrow-sway-bars.462854/, one of the user was asking for sway bars for testing, and he posted the result on his own forum http://www.theoryinpracticeengineering.com/forum/index.php, it's also mentioned in the pdf :) This is what he said :

"Nick, the numbers I posted labeled as the endlink rate is the amount of force it takes to move one end of the bar up 1" with the other end fixed. The arb rate is actual rate of the part of the bar in torsion. I have a lot of other numbers for this stuff as well that I've calculated, so there's a lot we can do with it. I still want to compare these numbers with different spring rate setups and see what kind of balance we can get out of the car.

Jero, I'm not sure what bars Dan actually has. They seem a lot stiffer than the advertised rates for different TRD bars. I thought they seemed a little stiffer than expected, but all the data came out about the same. The way I tested them is I loaded them with a different amount of weight and measured angular deflection t each end. And then calculated the rate based on the actual deflection for each different amount of weight. So for example, if it moved 1degree with 15lbs and 5degrees with 75lbs, I would use those numbers. This seems to be the best way to get the most accurate representation of the bars. Analyzing each step rather than overall deflection and overall weight seems to add more fluctuation in the rate due to the tolerances that I'm working with, especially on stiffer bars.

But I do have a lot of Mk3 data, so that should help with your track car project.

Tim
---------------------------
Tim, we all owe you a huge "thank you" for setting this up and collecting data. It's really nice that the numbers compare with what my gut feeling was. The rear bar that came on my car was WAY too stiff. The car was a complete handful and prone to snap oversteer. Each of the instructors that drove my car spun as well. After putting a stock rear bar on, the car tends towards understeer unless you add a fair amount of throttle. Who knew that my rear bar was 5X stiffer than stock!

Now I have no idea what these bars are. They were supposed to be 1st gen TRD Big-A bars, but based on the rates you measured, they must be some unknown brand.

I did just buy a Tanabe front bar (chromoly, hollow) to try out. If I get a chance I'll send it your way as well. And if my local track stays open I'll probably eventually get a set of TMS bars that could be tested.

Thanks again!

-Dan"


I would suggest to read through the supra forum discussion to get full understanding of how he tested the ARBs :)
 
I got the pdf from automotive forum long time ago, it was referenced in a Supra owner forum https://www.supraforums.com/threads/want-to-borrow-sway-bars.462854/, one of the user was asking for sway bars for testing, and he posted the result on his own forum http://www.theoryinpracticeengineering.com/forum/index.php, it's also mentioned in the pdf :) This is what he said :

"Nick, the numbers I posted labeled as the endlink rate is the amount of force it takes to move one end of the bar up 1" with the other end fixed. The arb rate is actual rate of the part of the bar in torsion. I have a lot of other numbers for this stuff as well that I've calculated, so there's a lot we can do with it. I still want to compare these numbers with different spring rate setups and see what kind of balance we can get out of the car.

Jero, I'm not sure what bars Dan actually has. They seem a lot stiffer than the advertised rates for different TRD bars. I thought they seemed a little stiffer than expected, but all the data came out about the same. The way I tested them is I loaded them with a different amount of weight and measured angular deflection t each end. And then calculated the rate based on the actual deflection for each different amount of weight. So for example, if it moved 1degree with 15lbs and 5degrees with 75lbs, I would use those numbers. This seems to be the best way to get the most accurate representation of the bars. Analyzing each step rather than overall deflection and overall weight seems to add more fluctuation in the rate due to the tolerances that I'm working with, especially on stiffer bars.

But I do have a lot of Mk3 data, so that should help with your track car project.

Tim"

I would suggest to read through the supra forum discussion to get full understanding of how he tested the ARBs :)

Really good. Thank you. This testing method is quite, how to say it, "real-world applicable" it seems. I can already think of some potential inaccuracies, especially when you're attempting to calculate actual *wheel* rates, but it lines up so well with a calculation method that I'm going to consider it legit and save for further examination.

How would you like to be credited? Is @Ridox2JZGTE fine?
 
Really good. Thank you. This testing method is quite, how to say it, "real-world applicable" it seems. I can already think of some potential inaccuracies, especially when you're attempting to calculate actual *wheel* rates, but it lines up so well with a calculation method that I'm going to consider it legit and save for further examination.

How would you like to be credited? Is @Ridox2JZGTE fine?

Don't worry about giving me credits :) I found the infos long time ago from searching the net, by the way I also have these data on suspension ( motion ratios, spring rate, wheel rate, natural frequency, roll stiffness, king pin angle, caster etc ), it was mentioned on the forum thread I linked, it's from Tim, the same guy who did the ARB test. I will upload these so the images do not get resized. They are datas from suspension analyzer for both front and rear. ( http://www.performancetrends.com/SuspAnzr.htm )
 

Attachments

  • suprapts4.JPG
    suprapts4.JPG
    74.4 KB · Views: 42
  • suprapts1.JPG
    suprapts1.JPG
    77.2 KB · Views: 44
  • suprapts2.JPG
    suprapts2.JPG
    75 KB · Views: 37
  • suprapts3.JPG
    suprapts3.JPG
    76.9 KB · Views: 43
Last edited:
Don't worry about giving me credits :) I found the infos long time ago from searching the net, by the way I also have these data on suspension ( motion ratios, roll stiffness, caster etc ), it was mentioned on the forum thread I linked, it's from Tim, the same guy who did the ARB test. I will upload these so the images do not get resized. They are datas from suspension analyzer.

Very nice. You find data in the weirdest places. My geometry is a laserscan base and I trust it, but things like motion ratios come from measurements from other units. They're pros so I trust them but it's not like I was there to confirm even what height they were measuring from and if the arms were stock so you should probably always allow for some error in these cases. I've never seen two identical MR measurements.

Perhaps I'll also do a rough calculation based method for MRs as well to verify results.

PS: The rear is multilink, so the curves and IC and whatnot are most definitely not trustworthy out of SusAn, the curves in particular are most definitely *extremely* distorted. That's why you get measurements and simulate the multilink to verify ;). But just as a tip to anyone reading.
 
Hello ArchKyuubeey! I onced downvoted two of your Racedepartment mods because I thought "physics overhauls" did not belong into "Ac Cars" category. I was like "look at this dude! ANYONE doing cars is working on the physics, and he call his work "cars".. what nerve!".
I see now that you do a lot more that editing physics. You actually demonstrate a lot of knowledge. I'm not qualified to discuss it, it just shines as knowledge to my eyes.
So, I wanted to apologize, as publicly as I can.
Also: what does your name mean?
Also II: Where is Masscot?
 
Hello ArchKyuubeey! I onced downvoted two of your Racedepartment mods because I thought "physics overhauls" did not belong into "Ac Cars" category. I was like "look at this dude! ANYONE doing cars is working on the physics, and he call his work "cars".. what nerve!".
I see now that you do a lot more that editing physics. You actually demonstrate a lot of knowledge. I'm not qualified to discuss it, it just shines as knowledge to my eyes.
So, I wanted to apologize, as publicly as I can.
Also: what does your name mean?
Also II: Where is Masscot?
Hey,

Technically you're correct, but I'm afraid there's not a section for "Physics mods" and I honestly don't think anyone will actually find what they're looking for in "Misc". So I try to make it extra clear what it is from the title, so at least people don't think they're getting a completely new car, like they seemed to with the R34.

Your apology is accepted. With your reasoning, I understand how you'd come to the conclusion you did. Especially with the wealth of modders who are indeed just "editing". To be completely fair and honest I do reuse some KS tire values (Whichever ones are sensible) and their syntax in their inis (Why redo it for no reason?) and whatever IS actually correct on the car. Some things like AI I might simply leave untouched.

What you're getting however is approached fairly seriously with completely new suspension, aero, engines, often all of the physics relevant parts of the tires barring some generics and so on.

For example, the KS E30 DTM cars simply use KS E30 roadcar suspension geometry, while I went and figured out what they did to the suspension (Raised tubs, changed trailing arm sweep angle, offset balljoints and tie rod ends) and adjusted my own, scratch made accurate E30 rear trailing arm and the front geometry.

So in practice I went and graphed the new curves for the rear trailing arm because AC doesn't natively support trailing arm so you must re-engineer the DWB geometry completely to achieve the *same* effect as IRL.
As in, I did the math to figure out what the higher trailing arm link does to offset the curve higher in the range and adjusted the camber setup options and curve accordingly. Then I did the math to figure out what the lowered sweep angle in the trailing arm does to the curve and I remapped the curve and recreated it by modifying the existing geometry.

The sweep angle is the angle of the two front links which attach to the chassis. If they're parallel, it's a 0deg sweep angle and you will get 0 deg of camber change from 0 deg camber static, when your link reaches 90 degrees from static.

If there's say a 15 deg angle, it's a 15deg sweep angle and you will get 15 deg of camber change from 0 deg camber static, when your link reaches 90 degrees from static. So as you see, the more "semi"-trailing the trailing arm is, the more camber (and toe) change will occur. They lowered the sweep angle from I think 15 or 16 degrees to 12 degrees IIRC so that the camber and toe curve isn't so aggressive in the very lowered DTM cars, which means they can naturally run lower camber without radical adjustment plates and overall have a more stable camber curve.

"Kyuubeey" comes from attempting to put in my alias in various forms and failing and settling for a very popular character at the time, and somehow having it not be taken. :lol:

"Arch" is just what I've somehow been called for a decade or so.

My name here is because both were taken. :rolleyes:
 
You can't learn to drive from a book, dude. It's like trying to learn tennis from a book. Or guitar. Or f'ing ;)

Anyway, consider taking my advice. Anyone can try autocross (that's how I got started).

Here's a formula for you: Driving/Sim-driving = Sex/Porn ;)

As a learner, my take from this is: I should value what a professional writes on an Internet forum, but must ignore what a professional writes on a book.

Also: comparing apples and oranges is fine, depending on the professional involved.
 
I'm sorry; but this is Ross Bentley's book!

While you're essentially correct in the sense that, no, the book won't *teach* you how to drive without actually practicing it yourself, you're essentially dodging the subject and it really looks like you're implying Ross' thoughts don't matter just because he wrote it down. :lol:

Okay, whatever. I could probably be directly copying sentences that instructors have told me, or directly from the book, or directly from instructional footage and I would still be wrong.
Dodging what? What in the world does this strange quote have to do with trailing-throttle oversteer?

"ILLUSTRATION 30-5 A common error that many drivers make is "crabbing" into the corner, easing the car away from the edge of the track prior to turning in. That's cheating, and it's going to cost you. Be aware if your car is right against the track edge at your turn-in point."

1. The quote (which is a footnote to an illustration that you haven't even included) has nothing to do with your theory that a car should understeer when you suddenly lift. Which I showed very clearly is the exact opposite of what really happens. While there are literally hundreds of online articles devoted to the subject of trailing throttle oversteer (https://en.wikipedia.org/wiki/Lift-off_oversteer), there are precisely zero mentions of "lift off understeer". Anywhere. Ever. Including in this non-sequitur of a quote you've chosen!

2. Your only driving experience consists of playing a single simulator (not even a variety of them) and reading books about driving. Is that an ideal way to approach the subject of vehicle dynamics?

3. So I'm not dodging anything. I'm simply starting to feel that maybe you've invested so much time, energy and (perhaps) emotional capital into learning the intricacies of AC that you can't accept the possibility that it got certain things slightly wrong. AC isn't a religion. It's just a fun game with a lot of variety. It does many things well. Other things not so well. Take your car to a local autocross and you'll see that it didn't get trailing throttle behavior quite right (on a lot of cars - some, like Bazza's, URD and RSS are OK).

Does that make sense? You said that lifting mid-corner (with no application of brakes) should lead to understeer. Only someone whose entire driving experience consists of playing AC could possibly think that. It's totally counter-intuitive to anyone who's actually driven a car quickly IRL. But it does happen a lot in AC when it shouldn't.

Now can we move on? Until you've actually taken a car out and tried this, there's no point and I'm sure everyone is tired of reading about this stuff in a modding thread. The only reason I mentioned it was that I had hoped to impress upon a modder the need to have real drivers test your creations, and not just rely entirely on diagrams and "millimeter-perfect" measurements in the vain, quasi-religious belief that merely plugging them into AC will auto-magically spit out a great car. I don't believe that for a moment, and the really great modders I've spoken with don't either.
 
You're talking about stuff which we've gone over a few times already a few pages back if I recall, so kondor, I think it's about time we leave it be.
Like you're literally not even responding to my post. Nothing in my post said anything about lift off oversteer. Perhaps you have some tunnel vision, and if you *really* wish to continue, please, re-read everything. But like I said pages ago I believe, I don't think we're *actually* disagreeing.

Nor do I know where you get your other ideas from. I'm especially a bit confused at how I could have started physics modding almost half a decade before AC existed if I've supposedly only ever played AC. I suppose all those cars I've made (privately) for rFactor, GTR2 and GT Legends suddenly dematerialized as well. I mean, they don't exist anymore on anyone's HDD, so I suppose you're right. :lol:

Hell, I think somewhere I read that someone said I hadn't ever been inside of a car. I'm learning so many strange details about myself which I was unaware of from strangers on the internet.

Oh dear...
 
I bought this Alfa Romeo 4C Gr.3/GT3 converted from SPORT by an Italian modder I heard about in a Facebook post for €4, but sadly its skin looks messed up because he modified it like those URD/RSS/VRC cars:
custom-showroom-1565268682_orig.jpg
custom-showroom-1565269159_orig.jpg

Is someone of you here capable of reskinning it like the original one from that game and perhaps create a template for it too? Would love to make an itasha skin for it honestly. Here's the car I posted on my Drive:

Hello. you can have the contact of the type. I'd like a couple of cars from GTSPORT. thank you
 
You're talking about stuff which we've gone over a few times already a few pages back if I recall, so kondor, I think it's about time we leave it be.

:rolleyes: You started off with this but you just couldn't stop getting in your last paragraphs could you. But this is your usual modus operandi, not just here.
You refuse to be wrong in any way shape or form.

And where did anyone say about you not making other cars or when you started? Not anyone that I saw, but you just couldn't restrain yourself from posting it.

Almost every RWD car is designed to understeer if you're on the front lateral limit and lift off, and almost all of them will attempt to do that. Roadcars, racecars, whatever. The reason is generally in RWD cars so that you can accelerate efficiently, not being on the limit of the rear tires when you stop trailbraking and start accelerating.

This is where it all started, back on Monday. So yes, you spent pages talking about lift-off understeer.
Which you are so completely and totally wrong about that it blows my mind. Then when drivers like myself, Kondor and maybe Ted explained about you being completely wrong, you just kept dragging it out.

Its mind blowing to think, that you really think race cars are designed this way.
Yes, a race car is designed to go as fast as possible into a corner and then when rolling off the throttle (or lift off throttle - no brake) early-mid-late corner (to regain under steer once it starts), its designed to understeer or "push" off the track. :lol:

Just say you mispoke and misunderstood and move on.
 
Okay buttplug, I miss-spoke. I should have been very clear what I mean with "x-steer" and how it relates to yaw motion and travel direction. Think back to my "drifting is understeering" thing and you will perhaps start to make sense of it. Or not; either is alright. We can move on.

However, 2 posts above yours, kondor literally said "Your only driving experience consists of playing a single simulator (not even a variety of them)" which is simply untrue. I'm completely unaware of where this misinformation is even coming from: certainly not from me. I wonder what other kinds of assumptions are being made, especially when it has to do with how I dev.
 
Okay buttplug, I miss-spoke. I should have been very clear what I mean with "x-steer" and how it relates to yaw motion and travel direction. Think back to my "drifting is understeering" thing and you will perhaps start to make sense of it. Or not; either is alright. We can move on.

However, 2 posts above yours, kondor literally said "Your only driving experience consists of playing a single simulator (not even a variety of them)" which is simply untrue. I'm completely unaware of where this misinformation is even coming from: certainly not from me. I wonder what other kinds of assumptions are being made, especially when it has to do with how I dev.
No chance of you guys taking this row to pms? It's been going on for weeks. This thread used to be a great read.
 
I, for one, do not regret posting here as I received some very sensible appearing Supra data out of it which will help me to cross reference to other data in the future and determine the most probable approximation. So I gained a lot. ;)
 
Personally I've been learning a lot. Do you want the serial mod poster or simtraxx back instead? I don't.

Actually, neither seems like a good option! :banghead:

I think KJRacing81 is right. Maybe anyone who wants to argue about how cars do or don't handle – and what experience or knowledge they do or don't have – could start a new thread called 'Bloviating About Things You May or May Not Agree With'?
 
Last edited:
Question for kondor999:

Why do you use a photo of William Storey (formerly of Rich Energy) as your avatar? Do you actually respect him or are you just trying to make us vomit on our keyboards? :drool:
 
Last edited:
Question for kondor999:

Why do you use a photo of William Storey (formerly of Rich Energy) as your avatar? Do you actually respect him or are you just trying to make us vomit on our keyboards? :drool:

Perhaps if your character in your avatar on the right from Weird Science was associated with F1, you may have a point. :lol:

So version 1.0 of these are sounding close to completion. I'm sure some of ya have these older cars on your HD.
Sorry for the bad quality, had to contrast/brightness to even see the rear - thats been cropped :D

70265868-2590015801050267-851776728731746304-o.jpg
 
View attachment 850409
On the category on the right side where it defines cars by "Types", is that value defined in ui_car.json under class?
What value is this to modify?
A part of them are classes (race and street), the other part are tags filtered. You can change both, classes and tags, via CM. You don´t have to edit the ui.json itself. :)

I´m just making new definitions that I´ll publish on RD when halfway done. :)
Making the same for tracks too. Just trying to find good icons, logos.
Or if you´re interested, I can publish it sooner and you, or whoever wants, can help improving it. ;)
 
View attachment 850409

On the category on the right side where it defines cars by "Types", is that value defined in ui_car.json under class?
What value is this to modify?

It seems to be based on a number of inputs from the ui_car.json from what I can tell. So classics is filtered as anything pre 1980, prototypes seems to be based on having the tag - prototype, same with rally and drift. Race/Street seem determined by the class selection field. I'm not sure how many filters there are in total, but then I use my own tagging system even for Kunos cars.
 
Sharing a mod? Host it on GTPlanet Downloads. Free, public hosting for files up to 10GB in size.

Latest Posts

Back