Roger Long wrote:

Note how smooth the engine sounds with carb heat on when leaned to about a
100 RPM drop. Throttle was full open and CHT were right where they are shown
20 minutes later. This video was taken at 5500 feet.

I did this on a recent cross country flight, 100+ miles each leg. The
oil temps ran higher than normal, as well as EGT's. I wasn't running WOT
and was only at 3500' ASL. We don't have CHT instrumentation and what we
do have is analog...