Lacking many features seen in rival modern racing sims, owners of Assetto Corsa have flooded a vast array of sim racing message boards defending Kunos Simulazioni’s lack of direction in the on-going development of the popular PC racing simulator, soon to see a release on next generation consoles. Armed with numerous official blog entries and developer forum posts which state Kunos are meticulously modeling the inner workings of each vehicle to ensure unprecedented realism, the Assetto Corsa diehards claim the main draw of the simulator is the accuracy of the official car roster; allowing for those who will most likely never afford a Ferrari the chance to experience both the strengths and weaknesses of a car they could previously only fantasize about.
However, experienced Assetto Corsa modders recently cracked into the newest addition to the game’s expanding library of official Downloadable Content, and discovered the claims made by both Kunos and fanboys alike in regards to accuracy may be little more than generic marketing babble. Dubbed Dream Pack #3, the $10 expansion pack launched with the inclusion of the Brands Hatch GP Circuit, as well as nine new cars – some of which are newer models of cars already existing in Assetto Corsa. While the game launched in 2013 with GT3 variants of Mclaren’s MP4-12C and Mercedes’ SLS AMG, the third expansion pack included the successors to the aforementioned vehicles with the McLaren 650s and Mercedes AMG.
Within a day or so, rumors quickly circulated of Kunos directly copying car physics values from the respective older car models, into the newer cars offered as DLC. This caused a slight uproar, as the sim racing community blasted the creators of the Sareni Camaro GT3 mod a few months prior for ripping suspension geometry values from the McLaren 12c GT3 created by Kunos. If Kunos had been doing the exact same thing, not only did it make a bunch of people look like hypocrites, it called into question the authenticity of the simulation and made some wonder if Kunos had resorted to quickly churning out content prior to the game’s release on the Playstation 4 and Xbox One. Given the game’s emphasis on authenticity and as much real data as possible used when replicating each car, this would be hard evidence that the ideology behind the development of Assetto Corsa had been lost to personal greed, and a publisher with a poor understanding of a product they’d chosen to support.
Why does this matter? From the most basic standpoint, hardcore flight sims would be crucified by the armchair aviation guys for releasing an F-16 that performs identically to an F4 Phantom, so there’s no reason to not hold racing simulators to the same standard. If you want to dig deeper, as my boy ApexIsFree once said, refusing to ask more from the world around you can suspend your growth, and keep you in a perpetual state of childhood where quality is irrelevant. No, you’re not “entitled” for pushing developers to “get it right”; allowing them to settle into a rhythm of “just get it out there” is how we end up with less than satisfactory products, ones which dumb ourselves down and keep us in a child-like state. Striving for more instead of settling for less shows maturity.
Anyways, on with the show.
Revealed at the massive Goodwood Festival of Speed event in 2014, the official press release states major changes have been made to McLaren’s flagship GT3 entry since the introduction of the McLaren 12c in 2011. The improvements claimed to have been made to the newest McLaren endurance racing entry are not just marketing babble to appease man-children queuing up for launch night in front of GameStop. McLaren have poured hundreds of thousands of man hours into the development of this car, and spent millions of dollars in Research & Development to ensure it can win races. Video games only need to sell X amount of copies, regardless of their quality, to be considered a success. McLaren needs to win a global competition. Marketing babble doesn’t cut it on this level, as the very exclusive group of customers will promptly call you on your shit if your product isn’t up to par.
A more in-depth list of changes can be found on the Road and Track Magazine website, again listing several improvements the car has made over it’s older, clumsier brother. While a 12c-to-650s upgrade kit is available due to the chassis being nearly identical, the quick shelf life of the 12c implies it’s not the option most teams should pursue.
From these two articles, we can make a definitive list of elements that have been changed from the 2011 McLaren MP4-12c GT3 entry, and improved in the 2014 McLaren 650s. In no particular order, these elements are:
- Suspension Geometry
I’m sure y’all know where this is going.
An Assetto Corsa modder who wishes to remain anonymous has decrypted the official Kunos car data files for both the McLaren MP4-12c GT3, as well as the McLaren 650s, and sent them to us so we could compare for ourselves whether Kunos has faithfully replicated the differences between the two McLaren GT3 entries, or if they have simply copy and pasted physics from one car to another in an effort to push out more cars prior to the console release. Sim Racers will hope we indeed find subtle differences that indicate Kunos have replicated McLaren’s new car in an authentic manner.
But if you’re familiar with this site, you know that’s not going to happen. You can investigate the decrypted files for yourself by downloading them here, and if the Notepad format is a bit of a clusterfuck, copy and paste the contents of each INI file HERE for a traditional view of each document.
We’re not off to a good start. The brake performance is identical on both cars, despite both McLaren and third-party Road & Track Magazine citing obvious upgrades to the brakes on the 650s.
The tires seem to fare a bit better, with the hard compound racing slicks – ideal for long online races in Assetto Corsa – receiving noticeable improvements on the 650S as described by both McLaren themselves, as well as Road & Track. Whether this is based on real data is up for each individual sim racer to decide, but considering attributes like “rolling resistance” are a lower value on the 650s, it’s safe to say there’s at least some authentic adjustments being made.
The gearbox, something McLaren touted as a massive improvement in 2014’s 650s and was even praised by an independent review of the car on TopSpeed.com, is identical across both cars in Assetto Corsa aside from one thousandth of an inertia value. From what I understand, this value is the rotational inertia of the gearbox. Values that would improve the speed & quality of the gearbox to replicate the improvements McLaren have made are not replicated.
The aerodynamics seem to have been adjusted to accurately portray the new rear wing and overall vastly different aerodynamic profile on the 650s compared to the 12c. A full point goes to Kunos on this one, as they might have these two cars as accurate as possible without looking at the actual FIA homologation documents. As not everyone has access to important FIA paperwork, we can’t check this, but we’re confident they’ve got it right here.
But now we’ve run into trouble. Despite both McLaren, as well as Road & Track boasting about the overall weight reduction improvements in the 650s, Kunos has copied not only the identical mass of the 12c over to the 650s, they’ve also used the exact inertia values as well. This value is subject to change depending on the GT3 series the car has been entered in, but it raises a personal red flag after reading of obvious weight reduction improvements – hence the sale of an upgrade kit with replacement body panels – would they really come out to the same exact overall mass?
EDIT #1: I would also like to draw attention to the inertia listed in the Car.INI file above. To add my own two cents into this mix and delete two or three paragraphs from the original version of this post, inertia is calculated in a very complex format, by adding the weight of all components of the vehicle into the mix. An article detailing the process can be read here, and in the end it also pokes holes in the identical inertia value for both McLaren GT3 cars we’re looking at. With McLaren claiming to have spent time refining the material and objects inside the cockpit, as well as re-desiging the roll cage, this value should be inherently different, as secondary objects inside the car are a completely different weight.
Now, before we get into analyzing the suspension components, it’s important to analyze the right part of the INI file. When combing through the file in question, we’re explicitly looking for the wishbone mounting points, named with the prefix WBCAR or WBTYRE, as these will definitely be subject to change even though the 650s shares the same chassis as the 12c. When McLaren discussed revised suspension geometry on the 650s GT3, this is what they are referring to. The WB values are the position of the mounting points, in meters, with the overall precision of 0.1 millimeters, along the standard three dimensional X/Y/Z axis. In short, rarely, if ever, will these be the same when comparing any two cars.
McLaren themselves have made it clear that these values are different, so there’s no reason for these values to be similar with merely one or two numbers adjusted.
As we dive into the wishbone suspension portion of the document, we can see that the wheel hub mass is identical despite McLaren going through great lengths to design new wheels for the 650s. The 52mm wider front end track is also faithfully replicated, so I’m inclined to hand another point to Kunos.
However ,the wishbone mounting points are virtually identical to the 12c, save for a tenth of one value being changed for the top of the tire mounting position. This is the exact opposite of what McLaren, as well as Road & Track, have told us about the “completely revised” suspension in the 650s GT3. These values shouldn’t be anywhere near identical between the two cars, yet they are straight up copy & pasted. In terms of raw authenticity and simulation value, this definitely isn’t good.
It is important to give credit where credit is due, and I can say that Kunos have made a genuine attempt to replicate some of the upgrades unique to the McLaren 650s GT3 in Assetto Corsa, enough to make the cars perform in a slightly different manner under ideal conditions. However, I will also say that the abundance of identical values when they outright shouldn’t be there gives skeptical users every reason to question the authenticity of the car’s overall behavior, and what Kunos is doing behind the scenes. While the aerodynamic profile and tire behavior have indeed received reasonable changes to accurately portray the 650s GT3, areas such as the gearbox, suspension, and brakes have been largely copied from the McLaren 12c.
But we aren’t done yet. As many people have sent in supplementary information to benefit this article, we’ve been advised to compare two other, very different cars – the Lamborghini Huracan GT3 entry, and the Audi R8 Plus. You know, the street car.
As we’ve demonstrated with the two McLaren GT3 cars, the chance of two nearly identical vehicles sharing equally identical wishbone mounting points in real life is slim to none. Now, in the case of McLaren, you can play devil’s advocate and say there isn’t much harm in using this shortcut as they simply may not have enough data to build an accurate rendition of the car. But the fact that this phenomenon shows up again when comparing the INI files of the street legal Audi R8 with Lamborghini’s latest GT3 participant is… not good for determining the mindset of Kunos Simulazioni in regards to the recent batch of DLC.
So let’s throw in one more for good measure, comparing the Mercedes SLS GT3, with the more recent Mercedes AMG GT3. In an article on TopGear.com, a website not affiliated in any way with Mercedes, the entry mentions that the new AMG GT3 is much wider than it’s predecessor, the SLS GT3. This means every single one of the wishbone mounting points for the new car will be different, as the overall dimensions of the car have changed.
Upon examining and comparing the decrypted INI files of both the SLS and the AMG, a majority of the values have simply been copied from the old car, over to the new one, with one or two digits adjusted every once in a while,
I can’t deny what’s been presented to me, and before our conclusion I must thank the three different readers who’ve helped contribute to this article in their own special way. Three sim racing community members who wish to stay anonymous have played an integral role in composing this article, from supplying the decrypted files to analyze, hunting for the articles on the real-world cars, and lastly for explaining specific elements of Assetto Corsa’s INI values to me in a way that I can convey to the readers of PRC.net without causing people’s heads to explode. You guys made this article possible, and for that I thank you – this is the vision I had of PRC.net when I first got into this shit.
I am saddened that Kunos have chosen this approach when crafting post-release DLC packages for Assetto Corsa. Many unbiased sim racers, myself included, were initially drawn to the sim due to what was advertised as unparalleled authenticity. It is frustrating to see this “authenticity” can so easily be demonstrated as sheer marketing lingo, and even more frustrating to see fellow sim racers parrot this lingo in arguments supporting the alleged realism of Assetto Corsa.
The cold hard numbers don’t lie. The most popular and most talked about PC racing sim in the past handful of years is no more realistic than the Gran Turismo or Forza titles owners claim it to be above.