More speed!

[まっふる]

I want to make the　day speed faster
Is there a patch?

[CarThief]

Did you just start playing the game, or did you already get some progress with it? Since there is a research/unlock that lets you speed up the game from default speed to like x2 times faster.
You get new researches/unlocks from doing missions, so, make sure to do the missions when you reasonably can (especially the Control Team and Information Team's missions, as they provide critical basic functions and information).

But if you already have that speed upgrade, then alas, it won't go any faster, and i never heard of a patch or mod to make it go even faster.

[Grim Xzag]

"Is farming too slow or do you feel like an abnormality takes too long to suppress. Worry not, I have found a way of increasing the speed behond max and will not tell you how."

If you do want to increase the game speed without moding the game, use Cheat Engin.