Different FFB in VR and single monitor (latency?)

#1

hey guys! I’m trying to figure out why FFB is different when I’m using my VR headset and when I’m driving a single screen monitor.
Its hard to describe it but I would say its kind of smeared not a quite sharp enough.
On a single screen FFB is really different, its tight, clear and predictable. It gives me whole picture of FFB (contact patch with the track). in VR I feel the difference. I’m even hesitating sometimes to go on throttle or turn the wheel.

Could it be a significant input lag that can cause such difference?

I recorded some test:

game: ACC
track Barcelona
car: Porsche Cup (2022) (very sensitive car, and to push it to the limit is very important to feel every details from the wheels and track surface and to manage with the weight transfer as well)

tech specs:

VR: HP Reverb G2
GPU: 4090
CPU: 5800x3D
RAM: 16gb 3600hz (XMP)
WB: Simucube 2 Pro

#2

I sometimes have the feeling that FFB is even changing on the camera view I choose. Fe WRC I sense that quite a bit. Shouldn’t be this way, but I feel a difference

#3

You have recorded the mirror screen where as far as i have noticed myself there is a latency to that compared to what i see in my G2. If you are experience the same lag inside the headset too, then there is something off. Still i always have the impression that there is something different to the FFB when i am in VR but maybe it is my idea. I am not so much of a fan of ACC but this thing is not optimized for VR and even your 4090 cannot max out the settings for the G2. That might maybe play as well a role.

#4

One thing to remember and what is probably happening here is that there can be timing differenced between what you see on screen and when the information comes through the wheel. this can happen either in a positive or Negative timing depending… This is one of the reasons why iRacing with lower wheels sometimes feels like the car always wants to snap oversteer… as the Telemetry is saying you are over the limit but what gets to the the screen and or wheel is delayed from that moment… so by the time you get the information it is already too late to correct it… It has nothing to do with iRacing Physics but just the way delays affect perception. if the VR has a higher delay due to processing than the single screen it can make you feel behind the car and in turn reacting more to what the car is doing than being on top of it.

#5

Send the problem to Kunos. I’ve noticed the FFB changes depending on whether I’m hotlapping or racing the AI on ACC. This is so with my TM setup and my SC setup, so no fault on the hardware side.

#6

i think i have seen somewhere that fps can change the ffb in this game . Maybe the fps you are getting in vr are lower and that impacts your ffb . You could try to lower the settings just to test my theory. I don’t know if it could be usb bandwith ? But this is not easy to test.

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#7

on single monitor I set framelimiter to 90 FPS same in VR.

#8

I had a similar issue between my triple screen setup and my single screen setup. There was a small delay in my triples screen setup. The FOV can have a massive impact on how the FFB feels like.
I have no experience with VR but I imagine it’s more or less the same, get your FOV settings wrong and it will screw with your FFB.
In my case it turned out that the distance to the screens where slightly wrong when I used a FOV calculator.
I solved it by changing the distance until it match what I saw on screen and when I felt it in the steering wheel.
For me the distance where around 55mm to far away in the calculator compered to when it match in the game.

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#9

the thing is you cannot change FOV when you are driving in a VR

#10

Ok, what can you change in VR?
I kept the same FOV I only changed the distance to the screen.

#11

i understand that your pc is powerful , but setting a framelimiter doesn’t mean that those fps are sustained all the time that’s why i proposed to lower the graphics and try it again.

ofc as i said it could be related to usb bandwith but you would need to buy a rather pricey usb card to test that theory , but ofc if that only happens in acc then i doubt it is that. You could potentially try this out by keeping the wheel and the g2 in usb ports that are being controlled by different chipset , since most motherboards for am4 had two , you will have to read your motherboard’s manual to figure that out.

do you have the rev 2 cable ? if not i think you can get it for free https://www.reddit.com/r/HPReverb/comments/oyk6xd/revision_2_of_the_reverb_g2_cable_and_all_the/

#12

I can change virtual sitting position only.

#13

I thought exactly this, when I read the post. VR is imitating real life, and in real life you would change your seating position.

#14

Well, after clean ACC install and downgrading from win11 to win10 FFB is back to normal again.

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#15

if the problem was windows 11 , that is a serious problem.