My dad had this problem with the neighbour's cat (cat now lives with my dad), he used to puke too because he ate too fast so my dad only gives him small portions at a time, literally a spoon full, waits for the cat to finish, pause, next spoon full. It's tedious but kitty hasn't thrown up since.

And Timow, two of my father's previous cats died at the grand old age of 22, 14 is not particularly old for a cat.