Cars (DATA REPLACEMENT) Mazda RX-7 FD3S Improved Physics by Arch

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Can you tell me what you did to figure this out? I used the KS Spirit as the base for the drift version and keep getting the exact same errors but don't have any issue with the new Spirit version. I feel like I'm missing something very obvious.
Drift uses the Tuned visuals.
 
The car drives so much better- it feels fantastic and definitely more alive. I have one quick question however. I get the "suspiciously low transmission loss" error- is this due to the SI base units used for the torque or the adjustment of the power curve itself. As far as I know Kunos used a system that already factored in the transmission loss to define the curve. Again, many thanks for transforming the physics and I am by no means questioning anything you've done- only curious as to the origin of the message.
 
The car drives so much better- it feels fantastic and definitely more alive. I have one quick question however. I get the "suspiciously low transmission loss" error- is this due to the SI base units used for the torque or the adjustment of the power curve itself. As far as I know Kunos used a system that already factored in the transmission loss to define the curve. Again, many thanks for transforming the physics and I am by no means questioning anything you've done- only curious as to the origin of the message.
I think the discrepancy comes from the graphical UI being after losses, but the text UI being before losses. My text figures vary, but the graphs are always after losses, but CM seems to have an issue with that. If you put in your power loss % when generating the curve, it will make a before-losses curve; so CM is assuming there is "0% loss" or something when it compares them.

Transmission loss is a dynamic figure and not a constant %, so generally in empiric simulations like AC, you input the "wheel" values directly. Due to that I use wheel values in my graph because they are truthful. You can't really compare crank torque graphs.
 
I think the discrepancy comes from the graphical UI being after losses, but the text UI being before losses. My text figures vary, but the graphs are always after losses, but CM seems to have an issue with that. If you put in your power loss % when generating the curve, it will make a before-losses curve; so CM is assuming there is "0% loss" or something when it compares them.

Transmission loss is a dynamic figure and not a constant %, so generally in empiric simulations like AC, you input the "wheel" values directly. Due to that I use wheel values in my graph because they are truthful. You can't really compare crank torque graphs.
Thanks for the quick reply- so it's an issue with Content Manager getting confused then. For the Kunos cars, the power.lut file contains torque values consistently lower than those seen in the UI, implying Kunos used values at the wheel in the lut and engine values for the UI, perhaps approximated by a 15% to 20% loss or whatever. Thanks for tolerating my noob question- I'm new to this and recently got into sims.
 
i personally love the way the FD stock feels, but yours feel completely different yet i know that your data is more accurate. Makes you wonder what was going through the company's mind when they coded the stock FD. Thanks for the work, Arch.
 
To be fair to Kunos, they were probably thinking "we can't afford to spend 9 months researching and perfecting this one car, we have 150 others to make."

Modders have that luxury. This thing's been on the go for a long time... I've been working on and adjusting my WRX for 5 years. That's not something a company can really do. It's not profitable. :p
 
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To be fair to Kunos, they were probably thinking "we can't afford to spend 9 months researching and perfecting this one car, we have 150 others to make."

Modders have that luxury. This thing's been on the go for a long time... I've been working on and adjusting my WRX for 5 years. That's not something a company can really do. It's not profitable. :p
That's the gist of it. Although there are some very questionable implementations in some cars, and KS even stole some of my work for their R34 just because it was included in the original mod car and I've criticized them in the past for stuff like that, in the end of the day Aris had to make 10x~ the amount of cars I've released in roughly the same time, so I give him some slack.

Racing video game developers don't get very much or very good data most of the time and realistically if you do the math, KS had a maximum of roughly one week per car at the most, while modders are able to do research and develop a single car for as long as they want. This FD's been made for some two years now and it's not even >90% empirically accurate yet, and that's only because all of the necessary data hasn't been found yet.
 
Makes sense, but im still on side "Quality" over side quantity. Wow. Still not enough data for a car that has been going almost 30 years ago and a street one at that?
 
Makes sense, but im still on side "Quality" over side quantity. Wow. Still not enough data for a car that has been going almost 30 years ago and a street one at that?
Almost all of the good data comes from the manufacturer. Rarely do cars have communities around them with people who know what they're doing and correctly test stuff. Just "buying a real car" is not super useful either when they're this old and all of them are modified.

What I'm missing is relatively minor from now on though, when the next update comes. I determined motion ratios kinematically and found some Mazda drawings for the suspension geometry, so the important stuff has a decent basis to them. Also found damper curves for the Bilstein OEM dampers and the ones I'm putting on the driftcar.

If you really want a "simulation product" though you need to have a better effort than that. Preferably K&C for all of the kinematic stuff, direct IRL measurements of the springs and stabilizers, wind tunnel testing for the aero, tire testing and simulation etc. This kind of physics package is a tier or two below that, hence not >90%.
 
Funny enough i suppose that's all data that the manufacturer already has and doesn't feel like giving away for no reason? A shame, if only this was the only time i heard of Kunos having unrealistic cars in the game.
 
Funny enough i suppose that's all data that the manufacturer already has and doesn't feel like giving away for no reason? A shame, if only this was the only time i heard of Kunos having unrealistic cars in the game.
I would imagine any reputable manufacturer has at least all of the kinematics and mechanical specifications actually cataloged after testing and design. I've seen some report documents a few times and they're always incredibly long with all kinds of details that most motorists are not even aware exist.

"Full data" for a profilic, incredibly expensive car like the FD and NSX probably exists, but I don't think the manufacturer themselves would be able to find all of it in any short time even if they wanted to.
 
I'd be surprised if there weren't comprehensive engineering analyses for these things in-house, but... as for what gets provided to game companies, yeah, it's highly variable. I think the common perception is that "licensing brings all relevant data" but that's simply not the case every time. Probably not even half the time, but while I know the first is true beyond any doubt, the second is speculation on my part.
 
I kinda suspected that car data was a bit like info about medicines and vaccines, that companies WANT it to be made public to boast about it. Like the build manual for a car.
 
I kinda suspected that car data was a bit like info about medicines and vaccines, that companies WANT it to be made public to boast about it. Like the build manual for a car.
Just about every one of these legendary JDM cars I've made is worse in reality than in myth, so there's a good chance companies would rather write up some bogus marketing stuff than actually just release data.

Like everything else, it's just been getting more dumbed down over the years. I remember seeing some Japanese motoring articles from the 60's where magazines did scientific testing on tires and cars with similar tests that manufacturers do, just to have buyers be more informed. Now motoring journalism is all complete garbage devoid of factual content. I suppose a similar thing is happening in marketing.

Some select cars have a ton of data to them though, like the LFA.
 
Just about every one of these legendary JDM cars I've made is worse in reality than in myth, so there's a good chance companies would rather write up some bogus marketing stuff than actually just release data.

Like everything else, it's just been getting more dumbed down over the years. I remember seeing some Japanese motoring articles from the 60's where magazines did scientific testing on tires and cars with similar tests that manufacturers do, just to have buyers be more informed. Now motoring journalism is all complete garbage devoid of factual content. I suppose a similar thing is happening in marketing.

Some select cars have a ton of data to them though, like the LFA.

Just like how the Civic Type R didn't publish its 0-60 time to let journalists find out on their own?
 
Kyuubeey updated (DATA REPLACEMENT) Mazda RX-7 FD3S Improved Physics by Arch with a new update entry:

Get it while you can

31.05.2021 Version 2.7 Get it while you can

- Adjusted inertia (AC uses sprung input) thanks @JPG_18
- Adjusted CG
- Adjusted front and rear geometry based on Mazda schematic
- Changed some stabilizer parameters
- Changed motion ratios
- Removed "toe compliance" in rear
- Changes to engines
- Tire changes
- Minor aero changes

Read the rest of this update entry...
 
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