Universal M18 Operating Temp

[drh1965]

Would it be considered "normal" for the subject engine to hit 210-230 if driven to almost 3200RPM? Normally, it hits around 190 when cruising at 6 knots and 2500RPM. We had a wicked current/chop in the seaway this passed weekend and had to crank her up to make decent froward progress. The engine approached 230 but quickly cooled when dropped back to 2500RPM.

I'm planning to pull the HE for some maintenance but was wondering whether 230 is considered overheating/dangerous?