ok no way to the 185/55 it smaller than my current tyre. my external rolling diameter is small enough..
so if anything i'd like to go bigger on the rlling diameter.. fill the guards a bit more.
i currently have 185/60/14 with a diameter of 22.8"
if i go 195/50/15 it has the same diameter 22.8"
since i want to go a bit bigger then i have a chioce of
195/60/14 with a dia of 23.2"
205/50/15 with a dia of 23.1"
the extra contact patch on the 15 will give more grip but the extra sidewall of the 14 could promote more as well.