Normal vs Abnormal symptoms of running overheated?
 

I've got a tired moter in need of a rebuild that shows multiple symptoms when running hot. As soon as I get good airflow and lower temps to normal level they dissapear entirely and the engine runs great and pulls strong. What's normal and what is specific to a tired engine (180k with oil consumption of 1 qt per 400 miles)

1) Rough idle
2) Chain rattle
3) Occasional belt squeal
4) Noticable decrease in HP

Thanks!

My old SC would get hot at track days and would noticeably be down on power.
It otherwise ran fine, it did not need a rebuild however, but would have benefited from an upgraded oil cooler.