“ are rfactor2 physics broken” video

[green serpent]

Just in case you didn't catch all that F1 setup video, here is straight to an interesting bit regarding rear ARB. I think pretty common knowledge but interesting just the same. (sorry don't know if that worked, go to 21:00 mark)

 

[Nieubermesch]

The quality if the debate here would be greatly enhanced if you did read stuff fully before attributing it's cause.

I was just excited, but I was pretty sure it had to be only GT3 cars, just wasn't sure. I wonder why you only pointed that out at me, since two other people seemed to have missed what I was talking about, but alright

 

[Comante]

In all honesty these tricks won't make you faster if you aren't already, so it depends where you are and where you want to go. Are you a wannabe esports legend? Well you should already know these setup tweaks. If you learn how to make setup, then is your driving style that will dictate if you need or not those ideas

 

[mantasisg]

Biggest exploit is understanding things very well, then you can outperform those who are biologicaly faster and more precise, but has worse understanding and knowledge At least for a while before they figure out the details, or goes through trial and error longer than you.

Also thats why fixed setups are popular in simracing, which is a shame.

 

[cristianuk]

Ok, lets's check the facts. Roll resistance RF2 test. ( Sorry for the ugly graphics, it's not easy to install some cars in Developers Mode, but physics are not altered...)

160 kilopascals:
Top speed: 291.50 kilometres per hour

0 kilopascals:
Top speed: 290.58 kilometres per hour

So running four deflated tyres (totally deflated, punctured) translated into a loss of 0.92kph !!!!

In the video you can observe both runs. There is minimal difference on tyre footprint, minimal difference on tread temperature spread. Minimal difference in average temperature (56ºC for the inflated, 63ºC for the punctured.... the punctured tyres should be melting and smoking)
I forgot to show ride height difference: only 2.44 centimetres (naturally the punctured tyre should lose at least 13cm, the sidewall height)

With the help of telemetry I show that the tiny difference in speed is not even caused or atenuated by engine rpm difference, since engine power is virtually the same, and also aerodynamic drag Cx is the same for both runs, despite the change in ride height.

Of course I am not interested in running cars at 0 kilopascals. With this test I just try to say: How do you want to convince me that rolling resistance or any other force or energy is correctly represented for slight subtle pressures changes when even using a extreme pressure difference the impact of this change is so absolutely tiny?

The 'low pressures' issue is very important, because it is not something isolated from the rest of physics. If the ideal pressure to be fast is too low, this has an effect on tyre temperatures, on tyre wear, on car suspension rate, and in the HANDLING. Some people complains that some cars are too forgiving, can slide too much, almost drift, their response to steering input is too slow, bumps are almost not felt.
If sim racers could finally use higher pressures that would change a lot of things for the good. Not only telemetry data and setups would be closer to the real model. Also the feeling of the cars would be stiffer, more alive, reaction times would be stretched and in overall they would be more exciting, and of course, more realistic.

I don't attack the mistakes. I attack the fact that they are ignored, not admitted or, even worse, accepted as correct!
I post this with the hope that developers introduce a change in physics that might improve this subject, or that might introduce more freedom to define the pressure windows for roll resistance, grip, temperature and wear.

did you built the tires by your self or its an upgrade to an existing car to allow lowest pressure because that wouldn't work unless for sure you know whoever built the tires has generated look up tables for the tire to work from 1 kpa to 160 kpa or whatever, the myth still goes around that the minimum pressure is the fastest, its clearly not in fast corners

 

[Raintyre]

did you built the tires by your self or its an upgrade to an existing car to allow lowest pressure because that wouldn't work unless for sure you know whoever built the tires has generated look up tables for the tire to work from 1 kpa to 160 kpa or whatever, the myth still goes around that the minimum pressure is the fastest, its clearly not in fast corners

Those tyres include very low pressures of 20kpa for the tyre tests which generate the look up tables.
Anyway, I generated other tyres including 0kpa entries and the result is the same.
One thing is the theory. Facts are another, mate.

 

[cristianuk]

Those tyres include very low pressures of 20kpa for the tyre tests which generate the look up tables.
Anyway, I generated other tyres including 0kpa entries and the result is the same.
One thing is the theory. Facts are another, mate.

i made tests as well, the materials seam to be very stiff, i had to double/triple the load in order to make tires appear deflated, i think you need to make a custom material and generate a table with custom QSA table which is more complicated and very time consuming than making a normal tire

 

[Raintyre]

i made tests as well, the materials seam to be very stiff, i had to double/triple the load in order to make tires appear deflated, i think you need to make a custom material and generate a table with custom QSA table which is more complicated and very time consuming than making a normal tire

Once I tried using softer materials and the tyre increased size with pressure like a balloon