Disclaimer- I'm no expert

Most places recommend staying within 3% of the original size. Going to a 225/60/16 would be just over that at 3.44% or 22.5 mm taller tire. The "55" is sidewall height as a percentage of the width (55/100 x 225 = 123.75mm) The 60 measures up at 135mm.

Most online tire sites have a tech section with calculators to show all the differences between sizes. You might want to check one out.