What slew rate limit do you use (survey)

I know this feature on the Sport and Pro has been asked about many times. But I thought this would be a way to get more information.

So this topic is meant to be a survey of what users use for their slew rate limit. Not just people’s opinions on the Sport and Pro, but what setting people actually use. -Thanks!

  1. What do you set your value to?
  2. Did you arrive at that value through conscious testing?
  3. Do you have a Sport or a Pro?
  4. Any comments about individual games, or anything

I set it to 1.5 in iracing on the sport so the curbs are less sharp.
Can’t really feel its effects elsewhere unless I set it really low which just makes everything feel soft and round.


More SlewRateLimit - less time to reach desired Nm

I think/feel It is mandatory first to have correct UltraLowLatency on your profile prior to test with SlewRateLimit

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What’s the correct low latency filter?

Thats a very good question, I really dream with an automatic ULL option, where a simple test could calculate the time response between your system and SC2 hardware.
Meanwhile, the way to determine ULL is by feelings, and i feel that its Game dependant too

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Currently I am at approx 3.2 or so, Skew rate not only reduces the sharpness but it also limits the speed at which the wheel will respond in a quick motion. Using more will allow you to better feel the back end stepping out as you can hold the car in yaw more easily without the wheel deciding to snap back at a high rate or speed this snap back to center at times will cause you to be in a more tank slapping situation where you are trying to catch up with the wheel/game decisions. At this point you will only catch up when you have either slowed to close to a stop, Spun, or Crashed… Using skew is honestly I feel the most important filter on the SC2 to get realism in steering reaction. How much will be a personal thing on How SNAPPY you want the steering to be.

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Lets Talk about iRacing on this special case, because we all Know its 60hz ffb update rate and how It works. Correct me if im wrong,

Statement Iracing change signal every 16ms

TD set @10Nm Overall strength then:
-iRacing signal strength - 20% - 100% - 0% - 20%
-TD output strength - 2Nm - 10Nm - 0Nm - 2Nm

So we need to calculate an aproximate SlewRate Limit to achieve 2 to 10Nm in 16ms or less, then stop servo from 10Nm to 0 in another 16ms or less.

SC2 SPORT has a Max slew rate of 4.8Nm/ms

My calcs in a perfect enviroment give a result of 0.63 SRL MINIMUM (spongy feeling, never constant at any given streng because takes almost all refres rate to reach forces)

So, TD Overall force must be related to slew rate just like the weight of the steering wheel, diameter, constant filters and most important of all, Ultra Low Latency filter.

What do You think about It?

That would be true if you were not using any Reconstruction filter which is applied BEFORE the Slew rate… The Reconstruction filter interpolates the points in between and tries to represent the intended travel between those points and this NEW curve is what the Slew rate is applied to…

Another thing though would be that some of the spikes that we get in the games are lossless calculations meaning they are calculated based on minimal to 0 friction and inertia form the digital models of the cars so a quick change from 2 - 10 - 0 - 2 in some cases is at the source… In a real vehicle though you have manu other bushing, bearings, tire rubber, ect that will actually diminish the speed at which those forces come through the wheel… iRacing does say they calculate forces at the Steering shaft but the question will always remain do they have all the frictions and everything correct in the Tires, Rack, linkages, and bushings. and yes a higher refresh rate out of iRacing would also create its own possible slew factor curve between the points as opposed to a quick jump from one set to the next… But it is anyones guess as to If or When, a situation might come where they up the data rate.

As far as relating to overall force the question is really do you want it to reach all amplitudes at all times… and that is where it comes down to feel… I.e. that 10Nm quick jolt between 2, 0, and 2 could be a bump down the straight, yes it is harsh but in a normal car it would be absorbed more so in the sim you may only want to feel 3-4 Nm of that bump, therefore a larger skew would reduce that to feel more natural but in a longer strength transition it would end up reaching the full power… This phenomenon is actually more closely relates to why the Heavier servos feel more natural, or if you have a really heavy wheel on the servo it tends to feel a little less sharp, as that is what the added armature weight does (it slows the acceleration) the difference though is that Slew will limit the acceleration to in the case of the sport 4.8Nm/ms where a larger servo or heavy steering wheel alters the curve of acceleration.

This is really why slew is actually a great and useful setting is that it can take a faster servo and tone it down to a more natural feel which means that the feel at lower speeds where you are under the slew rate set will feel lighter and more responsive but as the speed goes up and the weights on the wheel get heavier and sharper the slew will keep them from feeling overly harsh by limits spikes but retaining the weight.

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