Simhub gives you a message when you try to model the tire slip. They say it’s not available.
It’s not terribad… it just feels less good is all. Just me being grumpy.
Part of it is that cars are heavy.
Yeah the information needed is there. And you can certainly feel/infer from the game data enough to drive the car well. It just is kind of weird how numb it is relative to kartkraft.
Theres that blank spot that all the sims miss, which is intital bite feedback. Kk was better. Iracing seems like it would really benefit from hydraulic actuators.
I think with cars, the vehicle compressing/expanding on the springs would matter a lot in terms of feel, under braking.
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Oh and hey, this is kind of cool:
https://socialblade.com/youtube/channel/UCrMRlCSk4v1JgtMtJPDHDJQ
Personally I think I deserve extra credit and a B+. B- is kind of harsh.
I don’t have hydraulic actuators (I have the mechanical actuators), but for me there was essentially zero improvement in tire loading/traction ‘feel’ when going from a static rig to motion. If is fun, and more immersive, but as far as actually providing additional sensory information that is needed to improve ‘feel’ it didn’t do it for me. I got a much greater increase in ‘useful feel’ switching from a belt drive wheel to a direct-drive wheel.
To clarify the braking from my perspective. For me, the most critical thing is to be able to arrive at the turn-in point and/or the Apex at the exact optimal speed, so that the other elements of the corner (tire loading, line, rotation, trajectory control) can be properly executed. IRL, the action, force, visual feedback loop makes this easy. In iRacing, for me, braking is more of a calculation; hit the brakes x hard here, hang on and pray, while kind of counting down to when I should release the brakes… it’s a time based thing instead of a feel based thing. And, for me, it gets doubly difficult when having to execute hard trail-braking maneuvers to carefully manage tire loads; it’s like playing a game of chance in iRacing, but it’s a game of perception and skill IRL.
Interesting. That’s a pretty good summary.
I think what I was playing with in my mind wasn’t so much tire as body. The way the chassis responds to braking and accel. In other words, when you hit brake, the sensation of weight piling up on nose. The way the energy cycle affects the car.
I guess the issue I have is that the energy cycle is not one loop; it represents the way energy movement, load transfer, traction (and resulting slip angles or % slip), and therefore forces that act on the car. This cycle starts with driving input(s) that request a certain level of ‘work’ from the tires, and then builds (slowly or quickly depending on the inputs) until it reaches it’s peak (the amount of energy needed to hold the tire in the deflected state laterally and/or longitudinal). If you are talking about a whole turn, than that peak is typically when the car ‘rotates’ it’s trajectory in the turn (aka end of the entry and beginning of the exit).
I don’t really have any problem sensing (and interpret meaning from) lateral slip angles in sim, which allows me to be tuned into the contact patch (where the work being requesting from the tire, and the load being provided to the tire, and the interaction between the tire and track, creates traction, slip angles, and forces).
However, trying to do the same thing for %slip (longitudinal deflection of the tire due to the energy cycle), and especially during deceleration, is very hard for me to feel in sim compared to lateral slip. It seems like the %slip ‘signal’ is so small, or the energy cycle, or the tire/track contact interaction, or the forces generated… something (or everything) just feels like a blind spot to me. I just can’t get (and/or interpret) that connection to the contact patches.
Anyway, my original hope for the 3-axis motion system was that I would have additional sensory information that would allow me to improve longitudinal traction sensing, but that was not the case for me. Obviously there are plenty of aliens out there who can ‘feel’ longitudinal traction, or have mentally created an alternate way of monitoring/interpreting longitudinal traction, but so far, this old dog has not learned that new trick.
I was thinking more along the lines of sim “info” generally as opposed to specifically tire in regards to motion.
Since the braking feel isn’t great etc, we sorta develop workarounds. You describe counting down to brake release, etc.
I was imagining that if you could feel the car “roll”, dive, etc that that might help inform things. Not so much what the tire is doing but rather the chassis/shocks are doing in regards to actuators. Maybe that sense of car moving about is helpful to that timing.
I have not found simulated motion to be beneficial. For me, the motion is interesting, but not particularly ‘informative’. That said, everyone is different.
I was hoping that it could be more than fun, oh well. Still, it does look compelling. The video of the guy in the kart motion sim looked really good.
This is why you and @speedcraft don’t like iracing braking, you have to be progressive or you are going to overheat the tyres
What are we looking at? I see a distance scale horizontal and % vert. Not sure what’s what.
Braking charts of VRS. Blue is VRS, Red is me. You will have to rework your braking technique to be more progressive if you want to get the correct feeling in iRacing
I am greatly disappoint that there are no alien laps for the open wheel c 2000 pm18. I don’t know why but it’s not popular.
I could transition back to usf or go do the big fast oval dallara.
I did buy the f3.
Maybe I like oval a lot because no braking?
Ah ok relative to alien…
Your trace is more vertical, more like what you’d expect to see in RS3 when looking at our karting braking. You then trail off the peak.
The alien laps are odd. In the first trace, it takes him 50m to get to pressure and he “reverse trails” in the brake, sorta like he’s driving at supercharged, using engine braking.
I have noticed that the wheels lock up very differently in racing as opposed to kk. The majority of my driving is no front brakes.
It seems like Iracing has a much narrower window to lock if you brake aggressively.
F4/F3 exists and feel better to drive tbf
You won’t lock but you will overheat the front tyres, which will make the front end feel numb.
I wonder why they would choose an unpopular car then for the oval/sprint C.
It’s actually better than usf2000 in some ways
@tankyx a long time ago you were getting me to be harder on the brake, more upfront hit, etc.
Are we now saying we are extending braking zones in search of balance/ sustained momentum?
So iRacing = not at all like IRL. 
I assume the corresponding VRS tire temp graphs also show that the tires are overheating?
@tankyx When you say
Is the braking induced overheating impacting the front-end feel in a transient way… so a brief impact on feel in the braking zone, or is it persistent… so it keeps building and impacts front-end feel for both braking and cornering?
Well yeah, but people argue that you need to be progressive with heavier cars, to give it time to load the front properly. I haven’t driven GT3 or GT4 so I can’t really say.
You can see (Dot line is my telemetry) that despite releasing my braking earlier, I never recover from being more aggressive on the brakes.
So it impacts you for braking and cornering.
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Interesting, thanks for sharing this!
What car were you driving?
Audi R8 Evo II, but it happens with all GT cars. Openwheelers/Prototypes are less sensible to that (but still a bit)
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