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How to upgrade from G920 - Recommendations?

Ricmotech's is well regarded, but $130.
Several other load cell kits convert the brake to a separate USB device.
I suppose you have seen this thread.
Yes, I've seen Ricmotech's loadcell. Kinda spendy, but at least its minimal DIY. That brings me to my other question: Is it only important to have the loadcell on the brake pedal? I thought it was recommended to have loadcells on all pedals. If not, great, because there's no way I'm spending $400 to upgrade Logitech pedals :roflmao:

As for the link to the other post, that's a bit too involved for me at the moment, but I still appreciate the share.

These wheels forfeit paddle shifting along with the button box.
Eventually converting a Fanatec GT or formula car rim to USB or Bluetooth addresses that,
but I use a separate TH8A shifter.
Yeah, I realize that I'll be without a paddle shifter until I can afford the button box. I was thinking in the meantime I might buy another cheap Logitech shifter and convert it to a sequential. This way, by saving money on the wheel, and the pedals, I'll have the money for the button box much sooner.

Ah, I see you've recommended the Thrustmaster shifter? I always planned to get the Fanatec shifter, but now I'm noticing a lot of people choosing the Thrustmaster?

I have seen positive YouTube reviews for the TrueBrake; something that is available now
and is an actual load cell for about the same price: Sensor Solutions FC2231-0000-0100-L
This load cell mod was described here by jspicer.
Here is the datasheet
Sweet, I'm going to do some research on Truebrake now.


I agree, going with Logitech pedals wired into the AccuForce controller, which provides 5V,
linear sensitivity and integrating pedals with wheel, so fewer USB devices.

A trick to linearize load cell response with Logitech wheel base:
  • swap wiring between clutch and brake, making the clutch nonlinear, but who cares?
  • swap brake and clutch assignments back in games, which may not be possible in all.
What's the deal with 3.3v and 5v?

A trick to linearize load cell response with Logitech wheel base:
  • swap wiring between clutch and brake, making the clutch nonlinear, but who cares?
  • swap brake and clutch assignments back in games, which may not be possible in all.
Wait, I'm confused. If you swap the wiring, but then reassign the pedals back in game, aren't you just back to the same input before step 1?
 
Logitech pedals with load cell for me was a significant improvement with my brake lines. I’ve recently upgraded to Heusinkveld Sprints and while they’re quite expensive, they’re an “end of the line upgrade”, meaning I won’t feel tempted for many years to upgrade them. Fanatec pedals aren’t in that same league so in my opinion, upgrading the G29 pedals and using them while saving to buy “endgame“ pedals is the more cost effective solution. That way you can buy the Accuforce sooner.
Yes, Sir, that's exactly my train of thought right now. Thanks for the input.


I agree; with tweaked brake and a digressive clutch hack, my feet don't mind G29 pedals.
Heusinkveld Sprints are aspirational, but would roughly double my sunk costs.
Are you saying its also possible to modify the Logitech clutch pedal to be digressive? That sounds awesome.
 

GeekyDeaks

Premium
Is it only important to have the loadcell on the brake pedal? I thought it was recommended to have loadcells on all pedals.
Personally, I'm happy to keep the accelerator and clutch as they are since in every car I have driven it's not the pressure I am applying to the pedal that determines how much gas or the biting point, but the actual position of it.

What's the deal with 3.3v and 5v?
The G920/G29 supply 3.3v to the pedals, so any load cell amplifier needs to work at 3.3v (most do).

Wait, I'm confused. If you swap the wiring, but then reassign the pedals back in game, aren't you just back to the same input before step 1?
Not quite. The G920/G29 wheel base takes into the account the little rubber block, so there is not a completely linear relationship between voltage and brake value. My buddy did a fairly detailed analysis using a DAC to plot it:
GraphReader-Linear%20Plot.JPG


The chart shows two things that cause some problems when you start messing around. First is the change in gradient around 1.7v/75%. It may not look like much but it's almost double the gradient prior to that, so in the region at which you try to threshold brake, suddenly the pedal becomes twice as sensitive. The second thing is the voltage range from max to min is only about 1.5v, which is less than half the reference voltage the ADC in the wheelbase is likely to be using, so you immediately lose half the precision
 
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Personally, I'm happy to keep the accelerator and clutch as they are since in every car I have driven it's not the pressure I am applying to the pedal that determines how much gas or the biting point, but the actual position of it.


The G920/G29 supply 3.3v to the pedals, so any load cell amplifier needs to work at 3.3v (most do).


Not quite. The G920/G29 wheel base takes into the account the little rubber block, so there is not a completely linear relationship between voltage and brake value. My buddy did a fairly detailed analysis using a DAC to plot it:
GraphReader-Linear%20Plot.JPG


The chart shows two things that cause some problems when you start messing around. First is the change in gradient around 1.7v/75%. It may not look like much but it's almost double the gradient prior to that, so in the region at which you try to threshold brake, suddenly the pedal becomes twice as sensitive. The second thing is the voltage range from max to min is only about 1.5v, which is less than half the reference voltage the ADC in the wheelbase is likely to be using, so you immediately lose half the precision

Cool, that actually makes perfect sense. So, Blekenbleu's solution corrects this issue?

Sure, several geometries.
Mine was inspired by this DIY G27 Clutch and Throttle MOD video.
Hmm, this is becoming another Logitech pedal thread..
Yeah, sorry about that. I really wish I could rename the subject of this thread "Upgrading from G920 - Recommendations?"

Once I get my Accuforce, I plan to make a new thread to teach other newbies what I learned through this process. Pay it forward.
 
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I made a DIY loadcell mod (https://github.com/GeekyDeaks/g29-load-cell), happy to help you replicate but you need a propensity for tinkering and access to a 3D printer. I would probably recommend the TrueBrake mod as an alternative (https://www.axc-sim.com/product/brake-pedal-mod-for-logitech-g29-g920-g27-g25-pedals/). It's technically not a loadcell, but the principle is the same (it measures spring rate compression, not angle). I'd also recommend bypassing the Wheel Base as I found that improved things no end for me with non-ABS cars
Oh yeah, finished my research on the TrueBrake upgrade. Yep! That's definitely what I'm doing. Not only is it cheaper, but its made to feel like a real care brake (which I care about as much as its precision).

You all are the best. I cannot thank you enough. I researched this stuff for hours on my own and got nowhere until you all came along.

:D:thumbsup:;):inlove:
 

blekenbleu

Premium
Ah, I see you've recommended the Thrustmaster shifter?
Not necessarily recommending; it's what I got instead of Logitech's
when I picked up my refurbished G29 years ago.
I always planned to get the Fanatec shifter, but now I'm noticing a lot of people choosing the Thrustmaster?
Fanatec's probably feels better. The TH8A is durable, but I missed too many shifts with it
until shortening its upper lever and swapping its cannon ball knob for cork.

I was reluctant to spend anything like Fanatec money when starting Assetto Corsa.
being unsure whether the lack of G forces in real track driving would be tolerable,
but SRS ShakeSeat's feedback somewhat compensates.
 
By the way, I found a very cool shifter alternative to the Thrustmaster and Fanatec shifters.

 
I was reluctant to spend anything like Fanatec money when starting Assetto Corsa.
being unsure whether the lack of G forces in real track driving would be tolerable,
but SRS ShakeSeat's feedback somewhat compensates.

Holy crap that's really cool :confused:


Now . . . how do I sell this to my wife so she doesn't leave me for being a total geek.
 
Sim Racing Garage reviewed the SHH shifter.
According to Barry, it (like the TH8A) offers only low shift resistance.
Cool, I just finished that review. Man that guy can talk for a long time. I appreciate his thoroughness, but maybe he should release a "summary" version as well.

Because the TH8A takes so long to switch from H mode to sequential mode, I still think I'm going to have to give this SHH a try. It will be way too long before I can afford anything else that easily switches from sequential to H shifting.
 

AccAkut

Premium
So if you disregard the chair, did you have much luck modifying your Logitech pedals? I'm still looking for a product to convert them to load cell.
has some photos on the later pages, its DIY all metal, with a loadcell from a Wii Fit board behind a very strong spring, so it's not totally solid like a Formula pedal. Heel&toeing works well, tho I've ofc trained on those pedals a lot before when they were still all poti based
 

blekenbleu

Premium
Because the TH8A takes so long to switch from H mode to sequential mode, I still think I'm going to have to give this SHH a try. It will be way too long before I can afford anything else that easily switches from sequential to H shifting.
I just stumbled across this seemingly credible shifter comparison video by R-VR Closet .
Take-aways:
  • SHH feel and mode swap are preferred over TH8A
  • Logitech shifter feel can be substantially improved at lower cost by 3DRap mods.
Barry also liked 3DRap G29 shifter mod improvements...
 
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I just stumbled across this seemingly credible shifter comparison video by R-VR Closet .
Take-aways:
  • SHH feel and mode swap are preferred over TH8A
  • Logitech shifter feel can be substantially improved at lower cost by 3DRap mods.
Barry also liked 3DRap G29 shifter mod improvements...
Another excellent find, my friend. That review just confirmed my confidence in the SHH.

The 3DRap mods for the Logitech shifter look excellent. However, the only thing I really need to upgrade my shifter for is the ability to quickly shift between H-shifting and sequential. I still can't believe Logitech downgraded the newer shifters by removing the sequential function!


. . . No obvious way to implement digressive clutch feel . . .

Is there an *easy* way to upgrade the Logitech clutch to be digressive? I saw your link to the DIY, but it looked very time intensive, and even if I had the time and tools, there were no instructions.
 
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I see 3DRap also has some very affordable upgrades for the Clutch and Throttle pedals. A Simple rubber piece that fits in the spring housing to harden the pedal presses.
 

blekenbleu

Premium
Is there an *easy* way to upgrade the Logitech clutch to be digressive? I saw your link to the DIY, but it looked very time intensive, and even if I had the time and tools, there were no instructions.
If you have access to a 3D printer, there are some that may be easier:
I see 3DRap also has some very affordable upgrades for the Clutch and Throttle pedals. A Simple rubber piece that fits in the spring housing to harden the pedal presses.
One can carve plastic wine bottle "corks" to suit...
 
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