Why is the engine frame-rate limited?

[Creid]

Fpslimit is a very welcome and needed option to prevent certain configs from rendering at >100fps and functioning as a room heater. I have no idea what you mean with 'same as vsync', vsync inherently lowers your framerate to a multiple of your monitors vertical refresh rate (lcds being 60h I assume). If vsync is off you can't expect to get rid of screen tearing simply by turning off fpslimit and reaching 80 fps.