Only know of a few on forums that may have the knowledge to answer to questions, but sure like all thoughts just for discussions. We have been seeing water pressure issues even prior to the CAT motors, and now I'm seeing things getting even worst.

Have seen a few threads talking about issues with boats and water pressure. Comments for Merc lead back to the poppet valves (such as on 4.5's) but I'm wondering is it just poor design. Similar issues are showing up with larger motors.

Is water psi that critical for these motors, and if so what are the pressure parameters?
What happens if a motor cruises from cold to warm water and pressure changes?
Would it help to install a larger pump to move more water and increase pressure?

If things like this cannot be determined why should (not would) anyone buy a boat with a CAT motor

Would really like to understand the issues and if I'm just going off in the wrong direction and missing the point(s)

Yep, good one
Guess I should have said catalyst first

There seems to be more and more folks with these issues showing up, and I would like to understand the issues with the designs.