Reader Submission #139 – The Official Mazda 787B

You’ve probably heard much rejoicing as of late from the Assetto Corsa community, as the PC version of the game has recently received a substantial software update that has been long-overdue for what has otherwise been a very incomplete racing simulator. Bringing with it proper pit stop strategy configuration screen as opposed to a Mario Party-like pit stall mini-game, the rudimentary implementation of driver swaps, and even a couple of new free cars from completely opposite ends of the spectrum – Mazda’s Miata and 787B Prototype, it appears the sim racing community have finally won out in the end. After years of staff members from Kunos Simulazioni angrily berating their users for “expecting too much” and “not understanding the purpose of Assetto Corsa” the team from Vallelunga are now slowly beginning to insert specific features and functionality sim racers have been requesting for years on end, indicating individuals the developers at one point labeled incessant whiners may have had actually had legitimate complaints about the direction of the simulator.

Regardless of how we’ve gotten here, I’d like to extend a thank you to all Assetto Corsa owners who risked multiple forum bans and being blacklisted by rabid fanboys for being very vocal about what the simulator lacked; it took a while, but Kunos’ recent additions to the simulator confirmed you guys were much more than just “trolls” and “haters.” Because of your diligence, Kunos are actually getting to work on making Assetto Corsa a much more feature complete piece of software. Good job!

However, with every twist, a turn. We have heard for several years that Kunos Simulazioni build cars within their simulator using an abundance of real data, often times pushing this element of Assetto Corsa to the forefront as a way to compensate for the shortcomings of the simulator – sure, there’s not been a lot to do until recently, but at least the cars are incredibly accurate, right?

Today’s Reader Submission notes that is not the case.

Hey PRC. There have been some posts on various forums about issues with Assetto’s quality of physics, or more specifically, the quality of the work pushed out by Aris under the Kunos banner. The fanboy army led by Stefano and his buttlickers seem to jump and try to dismiss legitimate discussions or questions. We have seen with many people, from banned users to the guy trying to find information for his mod based on his real life car. Having read a few of those hammered posts, I picked up on some aspects of what to look for thanks to the detailed info provided by the gurus and the nagging questioning brought up by certain users, including guys who DO release mods for Assetto. 

The Porsche from DLC pack 3 got postponed due to Kunos needing info, stuff missing, real life correlation, etc. Their words paraphrased. Well, how much of it is actually true? Do they really have the manufacturers go through everything and actually inspect the car? I call bullshit. That’s some yellow propaganda. Then to see them acquire mods and re-release them as holy grail content, as if the original mod wasn’t good or even superior, seems unfair. So with that information, the recent update and the possible flame coming up from the questions on the Porsche and the Mazda, I checked the following on the Mazda since it was freely available before. Note that all measures of CL and Downforce are in KG at 200km/h.

What you see in the picture above is the 787b with highest downforce achievable before the stupid loss that takes place. I’ve no idea how Aristotelis comes up with his stuff.

Next, we have the maximum downforce achievable while maintaining less shitty balance (still rubbish), so theoretically this is roughly the max downforce possible with 35% forward aero balance.

Third, I will compare everything to the other official prototype car, theCc9 they made which is Le Mans-specification. And remember, the 787B is supposed to NOT be Le Mans. Roughly this is the max downforce in a straight line.

Lastly, I will do the same as with the 787b, giving it a more functional 35% balance. The car actually makes a corner like Eau Rouge instead of just understeering off like a wooden box.

The value we have to look at is TOT CL: x.xx in the bottom of the app on the screen (I left the HUDs to be informative). The max for the 787b (1st image) is 2.8, the usable max is just 2.5cl. The C9 is 2.54 and the usable max is 2.39cl, so the range between the two cars (one Le Mans spec and one supposedly not) is 0.4CL at 200kmh, which equates to roughly 154kg of downforce.

Nowhere is an interesting thing that seems to relate to what the people are moaning about. The drag coefficient (CD) is much higher on the 787b than the C9 BUT the difference is the same as the downforce difference at ~0.4 CD (which = the .4cl range of downforce difference). With this drag you can say the car is not the LM-spec but if you go HERE and HERE (one of them was a link posted in the forums, I found the other from there. Great site!), the story looks wrong. There you find the downforce levels of comparable sprint-spec cars of the time. The C9 has cl of 4.47 @ 241km/h in 1989, the C11 has a cl of 5.36 at 241km/h in 1990. So the issue that follows is how the hell is the Kunos 787B, from 1991, performing at less than half of a car from the year before and much less than a car first developed 3 years prior?

So the main problem highlighted here is the downforce. The 787 is within .4cl of the Kunos C9 Le Mans specification but it is listed as a standard, non Le-Mans spec. So it is much closer to the C9 Le Mans spec than it is to the data suggested by the websites linked above showing the C9 Sprint (non-Le Mans) and C11 Sprint. Do they really pursue and get the information for the cars? If they do, why is it off in the game? What the hell are they doing to the cars to recreate them this way? I wrote all this for the Mazda but imagine the can of worms from the 2017 Porsche, being so different to real life according to mclarenf1papa? How can we trust that developer when they are consistently caught out with “alternative facts”?”

Kunos, in my opinion, likes to spin their information around with support from their fanboy army to portray an image that their content is always better, including the free mods they acquired. Their stance on waiting for data and a data sheet appears to be bullshit because you can right away check the downforce levels of the cars and how the diffuser makes no sense. Often the ratio varies wildly with higher ride heights generating over 100% of downforce. So when you feel the car understeer weirdly it’s because it went below the magic ride height number.

I personally doubt they have numbers for the latest Porsche as they made the claim. They probably had the company give the green light on the model and maybe engine, nothing beyond that. Meanwhile, modders get access to team manuals with legitimate air tunnel data and measurements. They are actually able to recreate the aero map very well (credit where it’s due) but Aris has no clue (modders words) about what he is doing. I don’t have time right now but if you extract the ACD from the cars, you’ll see the optimum heights and how it makes no sense how the downforce relates. Aris makes the diffuser have the wrong impact and instead of letting it stall at some point, it makes it not work.

People are circle-jerking over the latest update but I’d not doubt the 787B is much worse now than before IF they actually went over the original numbers made by the best guys. The Le Mans C9 had that issue of going below the magic ride height and losing nearly 100% of downforce. Now, the main thing we all know is you want the car as low to the ground as possible, just before scraping…. Not in Assetto.

Thank you for your very in-depth research, I must admit I’m a bit over my head here, but what you’re saying, as well as the data (and real-world tables) makes sense. I’d like to know as well how Kunos are claiming to have real data for cars, but the sprint variant Mazda 787b inserted into Assetto Corsa with the recent update has roughly the same downforce levels as the Le Mans spec Sauber C9. Obviously, it’s not right, and I hope it gets rectified. It also calls into question what other phantom numbers have been thrown into other cars, but we knew they did that already.


Reader Submission #138 – From One Extreme to the Next

After the surprisingly competent Porsche Cup release earlier this year, which saw a new iteration of iRacing’s long-standing tire model project impress even the harshest critics who had been slowly scaling back their activity within the simulator, iRacing’s latest update has now brought these specific tire model revisions to a slew of other vehicles as well. Dubbed NTM 6.5, the latest iRacing rubber redux has coated the forums in a film of optimism that is long overdue for the aging service, though today’s Reader Submission indicates not everybody is completely sold on the new changes as of yet. While certain cars are indeed much better to drive than they were previously, users are pointing out that tires have in some cases been hastily copy/pasted from one car to the next, in some instances leading to amateur rFactor mod troubleshooting scenarios which place slicks with inaccurate properties on the wrong car.

Wishing to remain anonymous, partially in fear of a backlash from the community for daring to talk to PRC, today’s Reader Submission has more.

Yeah, no introduction here, I just wanted to shoot you guys a short message about iRacing’s new tires. Very soft and spongy, if I have to cut things down for length.

It appears iRacing basically took the tires from the new Porsche GT3 Cup and slapped them on the HPD. While they solved the problem of skating on ice and being able to save death slides, they are obviously just a fudge of the tires in an attempt to try and make them act more normal-ish. It seems one of the main things they did was just make the sidewalls two inches taller. This added height makes the car wobble more, and feel very spongy in the first fifteen degrees of rotation in either direction of the steering wheel. It feels like running on tires with 12 PSI, where the shoulders are just rolling over. When loading an HPD setup from last season, the only thing wrong is the ride heights all the way around – they’re too high, and it doesn’t pass the built-in tech inspection.

As you may know, anyone decent in the Acura HPD runs their front spring rages from 160 to 210 n/mm, and then whatever their fronts are, the rears are a click or two softer. What’s funny, is that the spring range for the HPD is 130 through 550 n/mm, so effectively, the only viable spring rates you can use for the car are in the first 25% of their available range. And here is what happens now if you run within that range – the tire protrudes through the fender.

So suffice to say, I believe iRacing fucked up and put GT tires on a prototype, and it feels awful and completely unrealistic with huge sidewalls that make the car feel like you’re running on a sport utility vehicle suspension. I wasn’t even hitting the track with the front splitter all the way down;, obviously at Sebring that would be detrimental, but it would be even worse if you did. I was about four clicks up on each side from the lowest ride height. Back to the drawing board, I guess.

I’m certainly not trying to turn this place into an iRacers Anonymous meeting by any means, but what you’re experiencing is why people like myself, Dustin, and some of the commenters which frequent PRC often talk about the tendency for the staff to totally wing it, only for the low-level punters to sit there and sip on the Kool-Aid as if this is a perfectly normal part of software development with this much money and research behind the project. I could certainly sit here and throw out a bunch of insults directed at that specific neck of the woods, but instead I want to bring up a very specific example:

A few days ago, Billy Strange of Inside Sim Racing uploaded a lengthy preview video of the new build, and in it he discussed the new GT1 tires. Now, I like Billy, I like the concept of the video above – introduction skit included – so this isn’t a knock on him per se, but just an example of how the community operates and sort of looks the other way when it comes to genuine issues. About halfway through the clip, Strange begins evaluating the Corvette C6R GT1, and states that the car now feels “underneath you”, and previous builds had this weird off-throttle oversteer, or something to that effect. The portion of the video you’re looking for begins at 6:20.

My question is, why is this only being discussed now? When the last build was released, why wasn’t Strange coming out and saying “yeah guys, it’s not very good, the car doesn’t feel planted, it does some funny things, I’d be on the fence about buying new content.” Those are findings a lot of people would like to be made aware of. Instead, the fallacy of iRacers praising the new update and shit-canning the last build, when three months ago they praised that update and spoke negatively of the second-to-last build, continues, regardless of how contradictory they may be.

The point I’m getting at, is you are simply ahead of the curve here. You are correct that iRacing have a tendency to wing certain updates, and confirmation will come in about three to four months, when iRacers both on the forums and in YouTube videos will begin bashing this current build of the game. This is unfortunately part of iRacing’s development process; the in-house testers simply aren’t very good at what they do, and it’s impossible for iRacing to recruit aliens to test the software because it’ll then compromise the playing field (seriously, who would report exploits only they’ve found with $10,000 on the line), so the reality is that iRacing members are for the most part paying beta testers.

And to get these people to notice changes in the first place, you’ve got to make adjustments that go from one extreme, all the way to the other. Not everyone is the sim racing equivalent of Niki Lauda, blessed with sensitive ass cheeks and championship-winning driving skills. To get proper feedback on the new tires, they’ve got to make the change from one rendition to the next so drastic, even the punters (I like that term, thanks) with 1327 iRating feel obligated to hit up the forums and say “yes, I feel there has been an improvement. in these specific areas.”

Shitty? Yes, but that’s part of the deal when you sign up for iRacing. Some builds you’re racing, other builds you’re an elaborate beta tester. Now you see why some of us have taken the money and left for greener pastures.

Reader Submission #137 – iRacing and the Formula Renault 3.5 *UPDATED*

There’s a bit of a story developing on the iRacing forums today, and it’s one that you most likely won’t see covered on any of the major sim racing outlets, as it makes the team behind iRacing look extremely incompetent and lazy; willing to throw around thousands of dollars in licensing fees without anything actually coming of them. Today’s Reader Submission comes from a user by the name of Shannon and Nim are Ruining iRacing, though despite the obviously biased name, the entry is anything but – iRacing have teased the Formula Renault 3.5 for many months as a sister car for a vehicle already on the service – the Formula Renault 2.0 single-seater – but many have wondered why this car has not materialized in the same manner as the open-wheel ride pictured above.

We’ve now found out why, and it should make any iRacing member willing to spend hundreds of dollars on the service in the hopes of receiving a bunch of new content, question where their money is being put towards. In some cases, it’s merely being squandered.

Picture the scene. You’re running one of the biggest racing simulator services on the planet, and you acquire the rights to the Formula Renault 2.0 and 3.5. Excellent, a real coup that’ll bring in European racers in droves, which is good because that’s the market you’re weakest in. Finally, a proper ladder for the European road series. So you contact teams, and in true iRacing fashion, you find that you can’t get the data required to replicate the car.

Or do you even contact them in the first place?

In recent years, it has become quite commonplace for iRacing to announce something, only to never deliver. Long Beach is the oft-cited classic example, but we also have the Honda BTCC cars, an array of British motor racing circuits, the Silverstone update, various oval re-scans, and the list goes on. The tracks, perhaps, understandably got bumped, after all the Nordschleife and Le Mans were a lot of work, but what of the cars? Why don’t we have the Honda’s, the other three Aston Martin’s announced, the other BMW’s, and the Formula Renault 3.5? Even the Ferrari is seeming somewhat uncertain at this point.

Today, we have the answer, and it comes, like most information about iRacing, in the form of a post on the members-only message board. Way back, when people first began questioning the failure of the Formula Renault 3.5 to appear, a chap by the name of Diederik Kinds offered to introduce iRacing to a team he worked with, after iRacing had said they were unable to get any of the 3.5 teams to work with them. Now, that’s quite some stroke of luck. Sadly, the thread I’m sourcing has since been deleted for very obvious reasons, but thankfully I have taken enough screenshots to ensure everyone at PRC can understand the overall premise; those waiting for the FR 3.5 have come to know Diederik as the best possible route to getting this car in the game.

So the exchange starts with Tony Gardner himself:

Although we have no shortage of car production projects, it is our intention to build the 3.5 car. We are finally making some progress thanks to member Diederik Kinds who hooked us up with a good contact with a team this week who seems willing to work us. That was what we needed. Good job Diederik!

Diederik last posted on the topic in October of 2016, and we all thought that progress was being made, cars being lined up to scan, that sort of thing. Now it seems sensible that iRacing would be quite keen to work on this, after all they’ve spent money on licenses, and a license unused is money down the drain. None of us like to throw money away, and when running a business that is especially true, considering the number of loyal iRacing customers who will buy almost anything they produce, even if they never plan on driving it. The car would obviously have sold well, as evidenced by the enormous popularity of the Formula Renault 2.0.

Fast-forward to March of 2017, in a lengthy thread where someone asked if there was any news on the Formula Renault, eventually Steve Myers (the executive vice president and executive producer) eventually chimed in:

Sorry, nothing has changed here. I don’t own a 3.5 car and I haven’t found anyone that does that is willing to work with us.

He then quickly threw a distraction in there, saying fourteen cars would receive tire improvements. Initially the thread focused on the tire model changes, but eventually people started pointing out that there was a guy who said he’d work with them, and wondered what had happened with that. One chap wondered if iRacing just weren’t interested in making the car, given that the Formula Renault series isn’t anywhere near Formula One in terms of secrecy, so there wouldn’t be an obligation for teams to hide data from iRacing and refuse to work with them. Steve Myers did not take that observation very well.

If there is one thing I really don’t appreciate it is someone implying I am lying. I think anyone that knows me would vouch for the fact that almost to a fault I tell people how it is. If you can’t look at the roster of cars that we have built and figured out that we build what we get data for than that is your problem. We will happily build the car if someone can put me in touch with a team that actually will work with us and not disappear when they find out all the data we need to build it.

Now let’s go back again to how the deal was made. iRacing obviously spent money on licenses for the FR3.5 (and the Honda’s, the BMW’s and the Aston Martin’s). In many of those cases, they claim they couldn’t get a car to work with. Let’s think about that for a moment, just imagine how easy that is to take advantage of: “Yes Mr. Myers, feel free to pay me thousands for this license, now I’ll allow you to use our car in your game” is a pretty easy thing to say during a licensing deal if you know none of the teams running your car are going to let them do it. Money for nothing, right? And yet what business would actually operate that way?

So with all that out of the way, we finally receive the bombshell which exposes exactly how iRacing works. From Diederik Kinds himself, the chap with the contacts to help get iRacing the car if they really wanted it:

Just chew on that for a moment. It exposes a staggering lack of professionalism in iRacing’s approach. It leads to some big questions. Do iRacing really want the car? Do they rub team owners up the wrong way? Is there a communication problem? One has to wonder if, when one is bankrolled by a billionaire, one starts to get a bit lackadaisical about spending money on licenses that don’t get used. Perhaps when hiring friends, one doesn’t acquire the best negotiators. Is this what happened with the Honda’s, the Aston Martin’s and the BMW’s?

All of this money, all of these resources, all of these licenses, they send one Email, and then lie to the customers about teams being unwilling to work with them. iRacing haven’t even tried to get the Formula Renault 3.5 into the service, they basically sent an introductory Email and left it at that, but yet they’re paying for the license, and they’re doing so with the money iRacers have provided them with. You’re giving them money to acquire cars they don’t even put the effort into creating in the first place.

So just think, how many other times has this happened?

What am I supposed to do, act surprised? Everyone knows iRacing is a small team full of hobbyists and left-over Papyrus staff members that have been given a literal mountain of money to run their operation with, so it’s certainly not all that much of a revelation to learn a lot of bone-headed decisions are made behind the scenes, and the company on occasion will intentionally mislead or outright lie to their customers – like telling users a server outage is due to DDoS attacks, when it’s actually just the result of iRacers constantly mashing F5.

The most we can do is just continue to make people aware of it, and hopefully sim racers will either make smarter decisions in the future and not give a company like this their money, or simply continue to ask so many questions on the official iRacing forums, the staff can’t possibly delete every last thread on the topic without looking like they’re censoring criticism.

Which, of course, we know for a fact they do.

However, all is not lost. Because of the discussion surrounding the existence of the Formula Renault 3.5, as well as some of Diederik’s exact suggestions, Steve Myers has confirmed that they will now be looking into contacting another Formula Renault 3.5 team in an effort to finish the car for the European iRacing audience.

Unfortunately, this now raises more questions than answers. There have been several pieces of content announced by iRacing, only to vanish into thin air, and it took months of customers begging for information, passive aggressive answers from Steve Myers bitching about a team “disappearing” on them, and the guy who organized it all to start asking basic questions, just for one future car to get back on track. Will this process need to be repeated every single a time an upcoming piece of content vaporizes?

Reader Submission #136 – Picking Up iRacing’s Slack

2What if I told you there’s a way to unfuck some of iRacing’s most blatant shortcomings? That’s the theme of today’s Reader Submission here at, as an anonymous member of the service’s private Winstel Cup Series – a championship created to re-live the glory years of NASCAR’s fourth generation body style – has written to us explaining how the group of drivers were once under the spell of iRacing’s disastrous driving model, only to successfully experiment with key variables in the garage menu to produce an on-track product superior to the vanilla iRacing experience.

The result has been nothing short of spectacular; to this cluster of sim racers attempting to re-create Dale Earnhardt Jr.’s fantastic string of seasons flying under the Budweiser banner, iRacing has finally lived up to the enormous subscription and content costs the brand asks its users to continuously fork over each year. But it wasn’t without some work that really shouldn’t have been necessary in the first place, and today, we get to learn how they pulled it off.

3jpgHey PRC, I’ve decided to write this article for you guys because I feel like the community should know about what we’ve found within the iRacing software that makes it significantly better than the default game most of the users play.

I’m involved in a league called the Winstel Cup Series, which runs the K&N Pro Series car at large speedways to sort of emulate early 2000’s top level NASCAR events. On paper, this probably sounds like a surefire disaster, as iRacing tries this same kind of combination in the official mock K&N series every user can access by default provided they have the appropriate license level, but there’s a reason behind why these events are so brutal. Most of the fixed setups iRacing uses for this low-level series are above 53% cross weight, which makes the car handle like a dump truck. Usually, you have no front tires after about ten laps, and the car plows into the wall. This creates a nightmarish situation for anyone looking to have a good time from the car, and it gives drivers who have no clue what they’re doing, far too much confidence.

After our first season in the league, we switched to much looser setups that rewarded raw driving talent, and to our surprise, the average number of cautions each event dropped from a hefty six, to just three. The trickier setups also created much better racing, with the average amount of leaders and lead changes seeing a tangible increase as well.

We also discovered that tire wear within the iRacing software accelerates dramatically with hotter weather. In some cases, it’s downright unrealistic, completely contradicting the service’s goal of a highly accurate simulation. At the season 2 finale in Atlanta, in which we ran weather conditions of 90 degrees and clear sky,  we saw lap times drop off by three whole seconds in just ten laps. This is incredibly unrealistic, especially because iRacing’s scan of Atlanta Motor Speedway is from 2006, due to what the track logos are.

However, with this tire wear, we actually generated proper multi-groove racing. Atlanta, Charlotte, and Rockingham all lent themselves to a racing environment where every lane worked at both ends of the track, and during the closing laps at Atlanta, we had seven cars battling for the lead; everybody being able to use their own groove. However, four out of the seven cars still chose the bottom line, proving iRacing’s new surface model works, but not as well as they would like it to.

The next thing I’d like to address is the iRacing draft model. It’s broken to no end, and there are several problems that we could not fix to what we’d like, as it’s a problem with the sim itself. Some of these include side-drafting speeding the host car up instead of slowing it, and the last car in line falling out of the pack no matter how much draft there is. These problems can be reduced with the changes we’ve made, but they’re absolutely ridiculous in the context of a simulator. First, we put a 2.90 final drive gear in the car, which helped the racing tremendously. It seemed to be more like the 2001 NASCAR restrictor plate package than anything else, and we were able to have a good race, rather than the single file events iRacing usually puts on at Daytona and Talladega. Secondly, we added 250 kilos of weight penalty, which helped the last car in line not lose the draft as easily. We also kept the weather at 90 degrees and clear, which wore out the tires to about a second of fall-off, making the outside the dominant line during these races, and thus more realistic.

What we have done proves iRacing can be what iRacing promotes itself as, but it’s an oddity and takes a lot of work to make it right. You’re much better off picking up a sim like ARCA Sim Racing if you want something out of the box that works as intended, and makes it easy to find a league. However, I didn’t write this just to bash iRacing, it’s still the best sim racing service in the world, it just needs a lot of fine tuning.

urlThis sort of falls in line with what I’ve heard about iRacing’s atrocious default setups. Because of how many updates each car goes through, and how many cars there are on the service in total, plus all the different tracks which sometimes require alternative configurations, there’s simply not enough time for the staff members to create solid baseline setups for every single car to ship with every new build. The setups iRacing do churn out are often rudimentary configurations just to get new drivers around the track without spinning, occasionally carrying over from a previous build even if certain cars have received fundamental changes under the hood.

It’s very frustrating to deal with as an end user, as you’d think there would be some effort made to point people in the right direction – especially with how complex the garage area can be regardless of any mechanical experience you may have under your belt. And as a large majority of the popular oval racing series on iRacing rely on fixed setups rather than the ability to adjust your car in the garage area, only a fraction of iRacing members get to see the true power of the software.

I’m unsure why iRacing would intentionally cripple themselves in this department, and instead ship out god-awful baseline setups that are borderline retarded in a competitive setting ,when even their own users are figuring out how to work with the software, not against it. Their entire marketing gimmick is aimed at a hardcore audience who want something more demanding than literally every other racing game every made in the history of home computers, and people are paying top dollar (plus VAT) to say “I’m an elite sim racer.” So with such an influx of so-called hardcore sim racers who in theory should know their way around a pretend race car enough already to wheel a proper setup, why are they instead bundling the cars with configurations that are legitimately detrimental to the racing experience?

This is too stupid to be intentional; you seriously can’t tell me a bunch of guys in a private league somehow figured out how to make the on-track experience infinitely better, but then again, we’ve seen time and time again with iRacing staff that some of them don’t know what they’re doing, and are merely there as a reward for their time spent with NASCAR Racing 2003 Season.

Reader Submission #135 – The Use of Ballpark Figures

28724869973_b6587c4d8b_oOnly a few short weeks ago, the sim racing world was turned upside-down when Norweigan drifting personality and avid sim racer Fredrik Sorlie leaked a conversation between himself and Stefano Casillo of Kunos Simulazioni, in which the sim racer found himself on the receiving end of an aggressive virtual lashing from an otherwise respected developer within the sim racing community. While most of our readers rushed to take sides and either publicly blasted Stefano or accused Sorlie of being in over his head when it came to discussing tire behavior, lost in the community-wide argument was what the actual conversation centered around: tire behavior.

Casillo argued that the data and calculations powering the tire behavior in Assetto Corsa were the most important pieces of getting the virtual Ferrari on the screen to feel like a proper car driven to the edge of the tire, but Fredrik stated that his semi-random numbers inserted into the INI file – primarily the result of several trial and error experiments – produced a much more realistic range of vehicle dynamics on corner entry, which mirrored his own time spent blasting around the Nurburgring Nordschleife with his life on the line. Or, you know, something to that effect.

Today’s second Reader Submission comes from Richard Wilk, the in-house physics guru for rFactor’s Historic Sim Racing Organizationor HSO for short. The HSO website specializes primarily in full-length online races ahd championships held in machinery from an era of motorsports that placed speed over safety, either creating their own mods from the ground up, or re-building popular historic releases from the ground up to iron out their flaws. The website recently completed their highly competitive 1973 USAC championship to close out the 2016 calendar year, and are currently in the process of preparing for a 1980’s World Sports Car Championship event at Monza. Though these guys don’t receive much publicity on mainstream outlets, they’re busy as hell on their own little corner of the internet – consistently managing to acquire full grids for each and every event they hold.

ob_755803_cg1gkhAccording to Richard Wilks of HSO, you need more than just hard numbers – as Kunos Simulazioni have ruthlessly claimed when discussing tire behavior in private with real race car drivers – to create a convincing rendition of a virtual car, and it’s foolish to dismiss feedback from people who have driven the real thing, even if it goes against your own data. You’re building an experience, not a space shuttle.

1dac9a26393743cf75db3c55da1854146a8057d6Hello PRC! I’ve returned with another submission about the process of creating cars for all of your favorite simulators, but this time I’ve been a bit more outgoing than usual, and I’m finally comfortable revealing my name. You can read some of my past submissions HERE and HERE.

There was a lot of talk recently about Stefano Casillo from Kunos Simulazioni refusing to hear and even offending a guy with massive real life experience. To me, this is beyond unbelieveable. No, I don’t feel it’s appropriate to call names or question what Kunos are doing behind the scenes (though it may be a bit justified), but I’d like to explain to readers why this is all so preposterous to someone like me, who willingly spends his free time learning about cars, and creating a convincing set of physics for others to enjoy in a competitive setting.

As a physics modder, I can say that having a guy who not only drove the real thing, but understands how to be successful in a consumer simulator as well, and can flawlessly translate skills from one to the other, that’s pure gold. It’s already hard enough to find interviews or accounts from drivers detailing the real life experience because it’s not something auto racing journalists typically ask – they’re concerned about race strategies and other marketing things – so finding a guy willing to drive in a simulator for an excessive length of time  and even show you the way that the car behaves by modifying the files himself… I have to say I’m a bit jealous of Kunos that they have fans willing to go through that lengths to help the developers.

So for Stefano to shoot these people down… It’s very dumb. Honestly, incredibly dumb. But this gets much worse. You see, even if he believes he has his tire model numbers absolutely correct, he’s putting too much faith into two really dangerous categories:

  • That his physics engine properly translates those numbers into correct forces in all situations.
  • That his tire model is already perfect, or realistic.

Looking at point number one, I guess Stefano’s pride must have been hurt to lash out at Fredrik like that, so it’s no small wonder he doesn’t even question that his physics engine functions perfectly in all situations. But point number two is something he should very well question, because nobody, and I repeat nobody, can claim to have tires nailed in sim racing. And this is where feedback is most important.

When I sit down and work on a car for HSO, and this entails everything from helping with a scratch made mod our guys created down to every last lug nut on the wheel, all the way to tweaking an existing mod that people like but doesn’t drive very well, tires are the absolute last thing I mess with. You can do everything else right or get it somewhere in the correct ballpark, but tires? Its not just the grip. It’s the load sensitivity, the slip angles, or the relationship between front and rear slip angles, and how that all translates through the flawed or incomplete tire models we have, into car movements. This is a massive grey area, and you can’t rely solely on numbers, especially because those numbers powering other parts of the physics engine – or data that has to be extrapolated from other pieces of data – are not 100% reliable in the first place. This is where accurate feedback is crucial. Too many times I see things other modders have gotten wrong, because people just assume things about these cars, and never read or were bothered to ask people with legitimate experience.

I can understand modders getting this wrong, because Porsche or Ferrari haven’t given them free reign of their private garage, nor do they have the budget to acquire sensitive data or take these cars out to a track for firsthand experience, but developers themselves? A team who are supposed to know the inner workings of their software? It’s really inexcusable.

How can quality mod teams for Assetto Corsa exist, if the people creating vanilla content behave like this? They should be setting an example, not being yet another “I never sat in this car in my life, but I know better” autistic manchild.

1acfa9983bd05987f27314b3b2f1d1561e479838Even though we’ve sort of moved on from Stefano’s meltdown over Fredrik’s feedback and what it indicates about how Kunos Simulazioni operate, you raise an interesting concept that I’m sure the readers of PRC will appreciate (compared to a submission we posted earlier today, anyway).

When tires are still a bit of a black art that no single developer team – let alone real world car makers – have been able to master, why are Kunos behaving as if raw data and numbers they’ve set in stone are the answer to producing an authentic virtual recreation of performance driving? Consumer racing simulations – the ones we can buy off store shelves – are an approximation of vehicle dynamics using as much real world data that can be applied within the software, and then filling in the blanks with reasonable guesstimations. But physics engines themselves are an approximation of real life, using numbers to replicate the laws of the universe, so there’s no absolute guarantee the software powering these games is one hundred percent correct before we even place a car on the track.

Therefore, there’s no reason not to be open about feedback from avid sim racers with real world driving experience willingly plucking numbers into the game just to see what happens, because they might actually be onto something. And sure, let’s say after a ton of testing, their feedback results in experiments that are wholeheartedly inconclusive. That’s okay. It’s not a knock on you as a developer or as a person, it’s not them trying to undermine your years of obsessing over vehicle dynamics textbooks, it’s them saying “it doesn’t feel right to me, can we try going back to the drawing board so your software benefits me more on the real track than it already does?”

Unless there is something seriously wrong with your emotional state where even the slightest bit of feedback triggers immense hostility to anyone who crosses your path, this is how you improve the simulation value aspect of your simulator.