Be absolutely sure to remove the deadzones in the advanced controls. Any amount of acceleration deadzone will remove throttle control, and default settings have massive amounts of deadzone. It’s to the point where it’s actually possible to have better throttle control on keyboard by rapidly tapping the acceleration key then on a controller with default deadzones.
Making the first gear or two longer can also make the throttle control proposition easier. The default gearing setup when you upgrade to a racing gearbox is better tuned for everyday driving (where a shorter, more responsive couple of first gears are key). The exception to this rule are cars like the Jesko that have a massive torque spike. “Sacrificing” gears early to create very short early gears can help you quickly get over the torque spike, which makes throttle control extremely difficult. The idea is you build up the revs early in a gear where you’ll barely be moving, getting you past the torque spike without much loss of traction, then you hammer few a few gears until you get to your “effective” first gear. The revs will be above the torque spike now, making throttle control much easier. In the Jesko, my 3rd gear is my effective 1rst.
I play with no assists and I almost always try to keep a cars drivetrain in it’s stock configuration. It’s very possible to manage throttle on controller, even in S2 (though I recommend building up to that) but every car is different and requires time to learn, which is part of the challenge but also part of the fun!
Controllers themselves have different trigger travels, acceleration curves, and built in hardware-level deadzones. I’m a bit of a collector when it comes to computer peripherals, so I currently have and have tried multiple controllers. They play vastly different in driving games, despite having the same settings. My current favourite by far is the Sony Dualsense (ps5) controller. That’s partly because I’ve always been a bigger fan of the joystick locations on PlayStation, but the dualsense also has lots of trigger travel and has one of the easiest to manage acceleration curves. Meanwhile the second most used controller on my PC is the 8bitdo SN30 pro 2, and it’s built in acceleration curves is much harder to manage, along with the fact that it has less travel. I mostly use it for 3rd person games. Not as helpful info for you on Xbox but something to keep in mind.
One last thing: learn manual. Being able to control your gears is essential to bring able to control your torque (which is what causes you to burnout/lose traction). It is possible to learn how to control the car using trigger control alone, but you’re making things way more difficult on yourself in the long run, especially in a dynamic race environment. For example: some cars have way more stability while accelerating in a straight then accelerating out of a corner. This can be solved purely through throttle control, but it’s much easier and just as fast to grab the next gear a little early. Also managing the interruption of torque that changing a gear represents is much easier to learn when you’re the one activating it.
If you have games pass, download Art of Rally. It’s a fantastic little game that you never, ever want to play in automatic. The simplistic, straightforward look of the game will help a lot with learning the muscle memory, but the physics are real enough that you’re not going to pick up any bad habits. Just dial in your settings early, as they can really impact the game (for example, I can’t play with counter-steer sensitivity set to anything but %100). You’ll learn manual in no time playing that game.
Also it’s a great game.