How to tune Bumpstops

After testing many setup parameters and reading the dev blogs - in which Aristotelis mentioned they will be important with the ACC physics model - I'd like to dig in a bit deeper in bumpstops.

There isn't that much readily available info on how to setup bump stops of cars with moderate levels downforce. I only have some basic knowledge that it's a 'suspension travel limiter' that prevents suspension damage. But I feel there must be more up to it.

Can anyone provide me (or point me towards) a theoretical foundation of how they are supposed to work in combination with the rest of the suspension. And if possible practical tips how to set them.

Many thanks in advance

 

My theoretical foundation isn't the most solid on earth, to be honest, but I think the best tuning for bumpstops is: leave exactly as Aristotelis tuned them!
Second by a tiny gap: close your eyes and click randomly for 12 seconds.

No idea sorry, but it would be interesting to know, I second your request for suggestions/tips!

 

Just make them harder till the car is stable (take care with kerbs)

I have next to 0 idea too.

 

A quick write up on suspension setups in general.
https://www.paradigmshiftracing.com/racing-basics/step-by-step-race-car-setup-guide
And have a read through this.
https://steamcommunity.com/sharedfiles/filedetails/?id=451307434

 

As far as I can tell, their purpose is to keep the floor from stalling, so unless you're having issues with that you may not need to fiddle with them.
(Don't quote me on that.)

 

I think you need ride height data and suspension travel traces along with other telemetry data to stand any chance of meaningful tuning.
This is a must to really get under the hood and get the best out of setups including the aero.
Telemetry built-in and available in VR I hope.

 

At the moment we are a bit blind. If you don´t have telemetry or any visual indication i think it´s best lo leave it alone, but i think Aris said something that we will get some "tool" to see what´s going on.

 

Didn't Aris also say that in GT3 racing you're running with maximum compressed springs on the bumpstops, a lot? That would mean that we could basically treat it like a spring. One could take that assumption (!) to the test and set up - for example - soft rear bumpstops, then test if it somewhat behaves like soft rear springs.

 

Bumpstops don't act like springs because they have a "ramp" in the rates. The more they get compressed, the stiffer the rate.



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Like progressive springs then?

 

Sounds reasonable.

Another interesting question: are the dampers affecting those bumpstops, too or do they only affect the springs?

 

Not following.

Dampers are velocity based devices. Springs and bs are distance based.

Dampers technically "affect" neither.

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The dampers add a mechanical resistance to the expansion and compression of the springs, thus affecting their travel rate, don't they?!? How is that not technically a direct relation?

 

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He think means that springs exert a certain resistance given their position
(how far they are compressed). So a spring of 10cm that is compressed 5 cm exerts a certain force (statically). Dampers however do not exert a force when they are compressed. They only provide resistance to movement. So in comparison, a damper of 10cm that is compressed to 5cm does not exert any force in rest (statically).


Anyways. I've done some reading on bumpstop theory and application. Most people are 'right' regarding their application, since they can be setup to serve (very) different goals. Both preventing the springs from compressing completely, but also as an extra progressive spring. And I'm not talking about bumpsprings, which are the linear equivalent. So there is a lot to talk about.

Tomorrow I'll report some more detailed info

 

I'm aware of how dampers work. I just disagree when @Borbor says:

"Dampers technically "affect" neither."

So my question remains: will the dampers affect the travel rate of the bumstops in the same way as they affect the travel rate of the springs? I can't put this any clearer, really.