iRacing and Simucube 2

ah okay, what value don’t you understand? Maybe I can explain it to you.

Max Force is a scalar that maps between the Nm signal the physics generates to the 0-100% signal the wheel accepts. You can think of it as min(100, (ffbFromPhysics/maxForce*100)).

I am testing Wheel Force bar since last TD update.
For me, my feelings are that is another force scalation. With new Firmware Profile (37%overall force) FFb in iR at AUTO.
First time I put WheelForce bar at TD overallforce, but some cars I lose some feeling that can be achieved raising Wheel force bar.

For example, with Ferrari GT3 i need to raise Wheel Force bar at same Number as MaxForce bar=30nm
With RUF i’m ok leaving Wheel Force at TD overallforce

Max force is the Telemetry clipping point for iRacing.

If you set the Max Force for 20Nm everything above 20Nm that is generated in iRacings Telemetry will be clipped (flat lined)

So to achieve Maximum detail in feedback being sent to the wheel you want this number to be HIGHER than the Maximum usable telemetry of the car you are driving…

This point will vary by car BUT if the number is higher than the car being driven (even by a large margin) it will not affect the output.

i.e. If you set the Max Force for 20Nm cars such as the Miata, Solstice, Formula Ford, rarely the Skippy will get full fidelity but if you use pretty much any of the GT cars you will clip (sometimes heavily)

However if you set the Max Force to 65Nm almost all cars within iRacing will not clip as most cars will not put out usable telemetry beyond this point.

So basically you want this number the highest that it can be while still giving you the at the wheel strength you desire.

Which brings up another topic… Specific output - this is the ratio of the Max Force Slider to the actually Physical Output of the wheel… … This is why when you raise the Max Force the wheel feels weaker. the closer the Max Force to the Wheel Physical force the closer to 1:1 you will be with the Simulation Output…

This is also why it is best to run the wheel at 100% output with iRacing and then use the Max Force Slider to determine the strength at the wheel.

It is fairly easy to compare different filter settings and even wheels when the Specific output ratios are similar as the at the wheel forces will be relatively the same.

Now Wheel Force does nothing but alter the low Nm of the Max Force slider to the number set on the wheel force slider… this is a safety mechanism so that you don’t run specific outputs in EXCESS of 1:1 which has been the case in the past and lead to the can you drive this at 1:1 videos where in many cases they were running the DD wheels BEYOND 1:1.

I hope this helps… Most all of the above information and more is in the SimuCUBE tuning guides in the hardware section of the iRacing forum (first few posts).


If you set the Max Force for 20Nm everything above 20Nm that is generated in iRacings Telemetry will be clipped (flat lined)

Actually this confuses me even more :sweat_smile:
This is totally different to what David Tucker from iRacing Staff told me:

If you set it at 25 Nm you would get 1:1 forces at the wheel, Setting it to 50 Nm would give you 1/2 that amount…

Here is the Thread at iRacing forums:

He mentioned nothing about different settings for different cars.

So to achieve Maximum detail in feedback being sent to the wheel you want this number to be HIGHER than the Maximum usable telemetry of the car you are driving…

How do i know what is the maximum usable telemetry of a car?

You mean 100% in True Drive Software and adjusting with max force in iRacing?

What he said is correct… In that

“Or what is meaningful to set there, given the fact that i will use a Simucube 2 Pro with max torque of 25Nm”

and his response is “If you set it at 25 Nm you would get 1:1 forces at the wheel, Setting it to 50 Nm would give you 1/2 that amount…”

As if the Physical Wheel output is 25Nm and you set it to 25Nm then your specific output for the wheel will be 1:1 or it will match the telemetry output… What HE didn’t tell you and wasn’t really asked was how that relates to clipping and the full telemetry that the car will output… and this is where things become car specific.

Specific output is figured by dividing the Physical wheel output (25Nm in the SC2Pros Case when running 100%) by the Max Force NM setting… ie 25/25 = 1 (1:1) 25/50 = .5 (.5:1) and 25/65 = .385:1

Now in telemetry as an example the F488 GT3 will generally put out up to 40Nm in telemetry, this means that if you have Max force set to 25Nm iRacing will clip everything above 25Nm @ 100% (RED bar in the F meter) and the steering will go dull and lifeless but with a bunch of force… BUT you would be running 1:1 with the telemetry at your wheel.

However, if you were to run the Max force at 40Nm with the Pro @max you would be getting 100% output from the car at 40Nm which will drive your wheel to 25Nm and would give you a specific output of .625:1 or 6.25Nm at your wheel for every 10 Nm put out in telemetry… and the car would rarely clip or turn red in the F-Meter as you would be alowing the cars telemetry to be virtually unclipped…

Basically Unless your wheel can output every cars telemetry at 1:1 which would need at minimum a 65Nm capable servo motor you will always be running a % of 1:1 or a lower than 1:1 specific output…

Most people I have seen generally run between .35 and .45 but there are some of us that run more… I tend to run upwards of .6:1 but I have seen drivers running even stronger.

also in my research Most every car stops having usable telemetry around 60-65Nm however the higher the number the more fidelity you do get as you can recreate everything including extreme crashes as all telemetry would be sent to the wheel unclipped.

To answer the other questions…

You can find out the running telemetry You use on the car approximately by using the auto FFB setting in iRacing… as this will set the Max Force to the max telemetry the car put out during your sample run - a couple of % to take away spikes due to curb hits and things… I say take that number and add 5Nm at least to get a more true number… The only thing with doing this is some cars do have Max telemetry BELOW the wheel output capability (like the Miata) and this is where you can go beyond 1:1 if you don’t have your wheel strength setting set… This May also make the wheel heavier than you really want for those cars and so you will have to increase the max force anyway… Personally I would start at 65Nm and then drive the car you like most and if you need the wheel weaker increase the number if you need it stronger decrease it.

– Yes 100% in the True Drive software as this will allow the wheel to output force to its rated level… If you reduce this you reduce the wheel capability and it alters the Specific output.


Great, thanks.

This clears some things

This i very interesting. I have been playing with this value and in my head I also think that it should be on 100% in TDS (SC1 in my case). I have read and seen many SC users lowers this to 60-75%. Example, a streamer got a SC2 Sport and he runs it at 60% of 17nm = 10.5nm… (he only drives GT cars)

What I am wondering is what exaclty is he loosing by running the base at 60% in TDS? Details, force, bigger chance of clipping? in other words, whats the downside using a lower value. I know the upside is less force when crashing in a wall etc.

EDIT: As a side note i remember that with Fanatec v2.5, they said: never change the force on the wheelbase, always leave this at 100%. Only change the FFB force ingame.

(Game: iRacing if it matters)

Holy moly what a bunch of Mathematics :smiley: but atleast im glad you mentioned that the slider should be at 100%,because i was using iracings standard profile…but i dunno but my G29 feels even better then.
For the rest you explained…well i need too read it about 15 times i guess but im happy someone made a clear statement on how it works.
Thanks for that!
I was wondering so long already why i was clipping all the time,whatever i changed.

1 Like

this are my Settings for Skippy.
do you think that’s totally wrong or do you think it’s going much better?

There are a couple of reasons to lower the Main output of the wheel.

#1 - if you are using a game where the FFB system is a little overbearing and is not that adjustable in game.

#2 - if you wish to mitigate strong crash forces on cars that do not require the full range of the wheel… This is say you are driving the Miata in iRacing… that car will only need about 15Nm of telemetry for full fidelity. Say you are running at .5:1 specific output (50Nm on the racing Max Force Slider) with a Pro that means the wheel will only ever need to use 7.5Nm of its full capability to recreate all normal running telemetry… But what happens when you Crash and the telemetry spikes to 100Nm well the wheel will give you a shock of 25Nm because that is what it is being told is needed…

To mitigate this you can say run the wheel at 50% power (12.5Nm) and then lower the iRacing slider from 50Nm to 25Nm the will keep the .5:1 Specific output BUT when you get in that wreck you have no lowered the shock forces to 12.5Nm instead of 25Nm because you are clipping the signal earlier…

The only issue with this is you will need to make adjustments for every car (or Groups of cars) as the Telemetry range changes i.e the 25Nm Max Force would be too low for 75% of the GT cars to get full telemetry.

The Direct answer is you are compromising your fidelity when you lower the power, but that isn’t ALWAYS an issue depending on the car bing driven and the specific output you are wanting to drive with as long as you understand the cars telemetry output characteristics…

AND for those that will ask as it is inevitable - Nope there is no list of what cars will output as it is all based on the track, weather, and the way you drive. so that is where the difficulty comes in in doing specific power levels for each car.


I insist, using it like this is equivalent to exploiting it at 50% of its potential.

1 Like

Those are fine… The Skippy at max with the previous tire model only put out about 25Nm of usable forces (i.e. eliminating crash forces, etc…) I suspect with the current model it is putting out less given the feel… Since your Max Force is above that 25Nm (by a wide margin you are getting full telemetry from that car) so ou are fine even with the reduction of force in the TrueDrive software…

In fact generally unless someone WANTS to feel everything including extremes I say that once you get to 65Nm on the Max Force Slider you can lower the Wheelbase strength without losing really anything fidelity wise except for the really extreme cars, as 95% of all the cars in iRacing have nothing that is critically usable above 65Nm (or at least that is what I have found in my testing)


Yea it can seem very complex but it really isn’t.

Basically Max Force determines your Clipping Level (which needs to be at or above the telemetry output of the car being used) and the Ratio of your Actual Wheelbase Force (after % adjustment) to the Max Force slider number gives you what your actual “at the wheel” Specific Output forces will be based on the telemetry.

NOTE; You can have the same Specific output regardless of the % you set the wheel base power to which is where it gets confusing…

i.e. even a G27 with it’s 2.5Nm of power can put out .5:1 forces BUT the max force slider would need to be at 5Nm which would clip with absolutely EVERYTHING…

I did a few laps in the Ferrari 488 GTE earlier today,and it felt immediately much better,thank you!
Still have too tweak around but atleast what you said works.

Glad to hear, Normally things do feel much better when you get the full telemetry from the game… But yes it can be a little confusing until understood how it really works… That being said I do think iRacing has the best method of actually handling FFB strength because the wheel force is basically independent of the clipping force which means you can always get full telemetry AND the wheel itself will never to rarely clip itself unless you are running really really heavy filtering which I think with TrueDrive has been pretty much removed in favor of staying more in the helm of reality settings wise.

1 Like

Yeh i did some more driving yesterday and it really feels so much better.
I dont know what my Max force in game is but i thought i had it around 50 now and this are my truedrive settings:

And you are right it is far from clipping now,thank you sir,this helped me alot.
This was were i was searching at.

Im not sure but i think you should put youre wheel range at 900,because you have set it in TD,but not sure if that 8 degrees is noticable,or maybe you did it on purpose thats also possible.

I don’t know that either. But that comes out when I calibrate in iRacing when I turn my steering wheel 90 degrees to the left.