tire help for 96 gls

I'm having trouble finding a definitive answer on the max tire size (without rubbing on unmodified car). I have 16 inch wheels for my 96 jetta gls. They came with 205/40/16 euro T/A's. I was unhappy with the tires, rough ride and poor treadwear. Can anyone advise me with information? I'm looking at the "series" in particular. Can I go as high as a 55 "series" and have clearance for the wheelwell? Also tire recomendations would be appreciated!
Thank you,
Mike