Thanks Mark,,, I will look into it methodically and report back on this issue. I do know I have my engine timed at 25deg BTDC, My engine only has 5 hours after OH.
That would have been a useful thing to say up front :-). 5 hrs STOH is almost certainly the major cause of the increase in CHT's, with the timing possibly being a second cause. Like others have said, if it cooled before, it'll cool now - the extra 10 HP isn't causing a cooling issue.
