60Hz FFB / Slew rate / ULL / Formula help

Hi all, I’m finishing a new profile and I’m looking for as much information as possible about the slew rate formula and its ideal value for a SC2 PRO v2.

If I start from the software it’s as simple as: SR = 25 Nm / 60 Hz ? So, ideal Slew Rate value for iRacing is 1.50 ?

In my old profile, I based on a setup from 0 of “boxthislap” which indicated a SR value of 3.28 for SC2 with 16%.

Since iracing’s FFB signal is 60Hz, this equates to one piece of information every 16.66ms?

Searching the most realistic feeling like always :slight_smile:

Thanks for help,

There isn’t a formula for perfect slew rate. It’s personal preference. Higher will give sharper ffb and lower will give more smooth/soft ffb so just find what works for you.

I don’t think that’s right. the higher the slew rate, the faster the torque will reach the target regardless of the update rate.

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Wheel weight and diameter is more important than game freq.
Lately, im just tuning SRL only when changing steering wheel, It changes the acceleration somehow

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Thanks for your return.

Gonna try between 1.50 to 3.28 to find my optimal value.
(Ascher HUB-L with MOMO D30 32mm)

as @nirnav says… it is personal feel. Slew rate slows the speed of the wheel to reach the torque commanded of it which creates a more realistic feel because a Real car doesn’t just instantly reach full torque to the wheel… so adjusting this speed gives you that feel of loading the tires, Bushings, Rack, and all the other steering mechanics prior to getting the full brunt of the force being transmitted… 0 slew gives instant torque (equivalent to absolutely NO flex or slop in the steering - Highly unlikely in a real car steering system) while a higher number essentially adds all those variables in a way…

I run about 3.25 on my settings…

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Technically there is no “instant torque”, just different degree of slowness reaching commanded value.

Well yes true. It depends on the servo inertia and things like that. I said that in the theoretical sense in that is how the signal is being sent to the servo without slew… Hence the square waveform it is on/off with no delay.

May be we are saying the same thing, but slew is always there, when it set to off it’s just using max slew rate of the motor, which is 4.8, 8.0, and 9.5 Nm/ms for Sport, Pro, and Ultimate.