Engine Ops

[86BravoPapa]

Currently flying a TIO-540 Cessna single engine. I understand the proper operating technique of slowly reducing power during the decent phase to prevent shock cooling. However, what's the consensus of changes to manifold pressure once established in cruise; assuming it's within manufacturer's limits of M.P./RPM ranges?

Thank You

 

[86BravoPapa]

To add, and help gain a bit more insight about "proper" engine operation, what are the real prospects of shock-cooling or, in general, damaging the engine or failing to reach TBO do to power changes throughout typical flights.

i.e changes in M.P. from 25" to 22" or 20" in cruise at 24 or 2500 RPM? Running over-squared, which seems to garner a lot of differing opions, etc.

Abrupt, frequent changes or quick decents come to mind with airshow pilots, skydiving, tow pilots and, in particular, Bob Hoover who supposedly routinely reached TBO.