Hi!

I have been practicing a lot lately to get better in GT3s. I am looking for a group of drivers to join. I’m relatively quick (currently 3.4K), but I want to improve a lot more and my goal is to hit 5K by the end of the year. I am data-driven, love telemetry, love improving and I’m always looking for that final tenth :) I‘m a good team player, and really enjoy helping and supporting my team mates.

I figured being around faster guys, practicing and exchanging tips, sharing telemetry, just sharing stuff really, would be a lot more fun than my current journey.

(I understand a lot of you guys are doing the N24 so this might not be the best timing but nonetheless here I am)

I’m a chill dude from Quebec, Canada. Speak English and French. I’ve been on iRacing for 7 years, but I’m recently taking this a bit more seriously and with more dedication as I have more free time.

I’m a bit of a geek (software engineer), I love data and have a super analytical mindset. I live for telemetry, Garage 61, and granular analysis Haha. I thrive on technical critique and love a good feedback loop. I just enjoy improving and helping other improve.

Thank you!

Alright after that late wave of vibe coded apps, here’s something that’s different, is completely free (apart from a SimHub license!), and will hopefully make a big difference in immersion and possibly your laptimes! (It’s just scripts that you can use in SimHub to send signals to your bass shakers)

So yeah, I developed 2 small scripts to help feel what the tires are doing; ie., are the front tires sliding (understeer) or the rear tires sliding (oversteer).

It took a lot of tweaking and testing, but I’m reasonably happy with the results. It helps a lot feeling connected to the car. Obviously we don’t have G forces telling us what’s happening with the tires so having an effect triggering when the front tires aren’t biting or when the rear starts stepping out is really cool and immersive IMO!

Requirements

• Simhub license (you should own this already, best simracing software bar none!)

• At least 1 bass shaker (2 ideally)

• At least 1 dedicated sound card or sound channel (at least 2 ideally)

Setup

iRacing LFE effects

Adjust as you want but here’s what I use and find really nice. Assign this to your rear/seat shaker

iRacing LFE bass shaker config

NOTE: I use . and , as keybinds to tweak the iRacing LFE effects strenght in the car. Don't just blindly use my "Main Intensity" (-10 dB) setting, tweak it as you like.

Simhub FRONT shaker (understeer)

1. Add a custom effect in SimHub "ShakeIt Bass Shakers" plugin

Add a custom effect using \"+ ADD EFFECT\" in SimHub

Chose \"Custom Effect\" in SimHub

2. Rename the effect "understeer" and give it a specific channel (FRONT). Set the frequency to 45Hz as a starting point (see note below), and make sure you put it in Mono mode so that we can use any tire as an effect source (we'll pick Front Left to setup the effect script).

Setup the \"understeer\" special effect SimHub integration

IMPORTANT: I use 54% at 45Hz for this shaker effect. Adjust this depending on your rig "frequency mode", try different Hz and different intensity (54%) until you really feel the most vibration in your chassis. Some chassis could resonate a lot at 30Hz, some others at 50Hz. This is really up to you! Hit the "Test" button and customize this until you really feel a huge vibration. Don't worry, the effect scales linearly with understeer so a tiny bit of understeer won't shake this much in the sim!

IMPORTANT: Tweak the intensity (54%) and Base effect frenquency (45Hz) to your liking

3. Add the custom script to the effect by clicking EDIT on the Front left tire effect. It doesn't matter which tire you use, as we use the Mono mode.

Setup the \"Front Left\" effect for understeer

5. Paste this javascript inside the Front Left "EDIT" script window. Make sure you tick "Use javascript"!

   let steerRad = Math.abs($prop('GameRawData.Telemetry.SteeringWheelAngle'));  let sway = Math.abs($prop('AccelerationSway')); // m/s2? let speed = $prop('SpeedKmh');

   // Convert Radians to Degrees (90 degrees physical will now be 90 in code) let steerDeg = steerRad * (180 / Math.PI); 

   // No understeer under 50 kph, we don't race this slow :P if (speed < 50 || steerDeg < 10) return 0;

   // UNDERSTEER (Front tires scrub) // Logic: At speed, steering should result in proportional sway. // if sway/steerDeg drops, the front is sliding. // at 120kph, we assume ~0.25 m/s2 per degree of steering

   // 120 kph, 0.25 m/s2, 1.8 gain are arbitrary values that could  // be tweaked for different cars.

   let expectedSway = (steerDeg * 0.25) * (speed / 120); let understeer = 0;

   if (sway < (expectedSway * 0.8)) {     // We use a 1.8 gain to increase understeer feeling     understeer = (expectedSway - sway) * 1.8;  }

   // return value between 0-100 return Math.min(understeer, 100);

Simhub REAR shaker (oversteer)

Rear shaker (oversteer) effect config

Same goes for oversteer. Create a Custom effect, rename it oversteer, set it up in Mono mode, Adjust intensity (24% for me right now) and Base effect frequency (70Hz for me, i like a higher Hz on oversteer).

Here's the oversteer effect code:

let speed = $prop('SpeedKmh');

// same as understeer, we don't shake under 50 kph
if (speed < 50) return 0;

let velocityX = $prop('GameRawData.Telemetry.VelocityX');
let velocityY = $prop('GameRawData.Telemetry.VelocityY');

// we calculate the car slip angle using the X and Y car velocity
let slipAngle = Math.abs(Math.atan(velocityY/velocityX)* (180/Math.PI));

// we assign a minimum and maximum slip angle: 1 to 9 degrees
// anything under 1 degrees won't shake, and shaking will increase
// linearly between 1 and 9 degrees. Most car have the most grip at 
// around 5 degrees (mid point), so your butt will learn this and
// you'll get a great sense of what vibration in your ass equals to
// 5 degrees :)

const minSlipAngle = 1;
const maxSlipAngle = 9;

if (slipAngle < minSlipAngle) return 0;
if (slipAngle > maxSlipAngle) return 0;

// map slip angle linearly, so that 
// 1 degrees equals 0% shaking
// 9 degrees equals 100% shaking
return ((slipAngle - minSlipAngle) / (maxSlipAngle - minSlipAngle)) * 100;

Assign audio channels to your effect

Map your soundcard channels to the correct effect

Ideally, i would assign understeer to your front shaker and oversteer to your rear shakers. But if you only have 1 you can assing both on the same, it should work as well!

That's it!

Give it a go and let me know how it goes for you. It’s tweaked for sports car. I’ve tested it with GT3s, GT4s and the GR86.

If there’s something you think doesn’t work well for you let me know, I might be able to help you tweak the scripts or the config.