Lunch Lady already has an FPS Cap, however it is capped to 60 FPS which is generally considered quite low in modern games.
A 60 FPS cap has upsides but it has many more downsides.

These are some reasons that you may want to consider keeping or modifying the FPS cap.

60 FPS

• Can have much more input lag than higher frame rates (especially on higher refresh rate monitors)
  
• Can appear very stuttery to gamers that are used to gaming at higher refresh rates
  
• Running the game the way the developer intended it to be and has optimised it.
  
• Less GPU usage, meaning less power usage (can be important for laptop gamers)
  
• Better for streamers on lower-end hardware

Modified/Uncapped FPS

• Game is much more smoother at a higher frame rate (requires a higher refresh rate monitor)
  
• Not properly utilising the hardware that some gamers have spent thousands on can be quite frustrating
  
• Less input lag, something that is extremely noticeable to gamers that play at competitive levels, is the input lag that occurs when playing at lower frame rates
  
• There are benefits to having your frame rate slightly higher than your refresh rate, but you can Google them, as I don't want this guide to be super extensive.

I hope this is enough information to help you decide if modifying the FPS cap is for you.

Bonus Tip
Refresh Rate is not the same thing as Frame Rate.
Refresh rate is determined by what your monitor is capable of.
Frame rate is determined by what your GPU is capable of.

• Close Lunch Lady
  
• Open an Explorer window and copy/paste this text: %LOCALAPPDATA%\ProjectCoop\Saved\Config\WindowsNoEditor in the address bar.
  
  
• Now open the file named GameUserSettings.ini in a text editor of your choice. (You can just use Notepad if you don't know what to use)
  
  
• Find the line that has FrameRateLimit=
  
  
• Change the value to the number you want to limit your FPS too. If you want to completely uncap it (not recommended) set it to 0.
  I recommend capping it at 120 as this game is not optimised to be ran past 60, but I find that 120 is a good balance when running with settings on high.
  
  
• See bonus steps at this point if you're interested..
  
• Save the file and close the editor.
  
• Right click on the GameUserSettings.ini file and select Properties.
  
  
• Select the option that say Read Only, then click OK.
  
  
  
• Close the Windows Explorer Window and Run Lunch Lady, you should now be able to see that it's running at your selected Frame Rate.

BONUS STEPS

• Set bUseVSync to False (V-Sync causes input lag, you want as little input lag as possible)
  
• Set FullscreenMode to 0 (This will enable exclusive fullscreen mode which has many benefits (inc less input lag) over borderless windowed)
  
• If you use a decent GPU (I have a 1080Ti) Replace the ScalabilityGroups with these options:

[ScalabilityGroups]
sg.ResolutionQuality=100.000000
sg.ViewDistanceQuality=3
sg.AntiAliasingQuality=3
sg.ShadowQuality=1
sg.PostProcessQuality=4
sg.TextureQuality=3
sg.EffectsQuality=4
sg.FoliageQuality=3
sg.ShadingQuality=3

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