How to split a new window horizontally but keep both windows the same width?

How to split a new window horizontally but keep both windows the same width?

My window originally was 80 chars wide, and when I C-x 3 I have to windows
both 40 chars wide. Is it possible that when you split the window it
automatically widens the whole program so that both windows are 80 chars
wide. I'm tired to resizing window every time.
The same applies to C-x 2 when I need two windows both 24 chars tall.