Ok there is a way to get this from a solo quick race weekend, what you'll need:
1. Your console on for 24hours (Obviously)
2. A micro USB cable to connect to your controller and console (So it doesn't shut off!)
3. To make sure that your console isn't set to auto shutoff in your console settings (Power & Startup, the '
Turn off after' setting).
4. Disable Idle screen notifications under your notification settings.
Firstly take out any batteries you have in your wireless controller and plug the micro USB cable into the top of the controller and then into the console, this should keep the controller on as it makes it a wired controller. If you're using a wired controller you're already set.
Now for the race itself, from the main menu select 'Solo' and pick any short track, I chose
Brands Hatch Indy, now scroll to the far right option with the laps on it and edit the following:
~Laps - 1
~Opponents - 1 (Just because)
~Press
and change the
Time Progression to REAL TIME, this is the crutial part.
Back out of the menu and pick a car you want, now start the race and sit your car off the track where it wont move. The AI car will complete one lap and then pit on the second. Now you just leave the game running with your car sat there until 24 hours has passed,
you'll know that 24 hours has passed in game as your lap time will have gone passed 1440 minutes now simply complete the lap and the achievement is yours!
Note: The game needs to remain the main open app on your console since if left in the background for a long time your xbox may close it. You can if you wish snap an app but it wont be very fun watching something in a small window whilst your car just sits there. BCFCBristolRed confirms that you can pause/switch to another app briefly without voiding the achievement so long as your lap timer is high enough.
Here's a video showing the setup and the race clock being at 1440minutes