VP TMD41a Best rpm

Hi everyone, newbie here.
Whats the best rpm to run TMD41a's at and whats the max for cruising?
I have 2 in a princess 30DS.

I like 3000 to 3100 for economy, however that may differ for you. My planning hull with a medium load responds well in this range.
However.... for speed vs economy I like 3400 to 3600 max. The engines will do 3950 to 4100 WOT, and I do run them up to that to rpm, but
only for a few minutes. On a side note, a water pump sized and shredded the belt, and the return run to port on one engine at about 3500 rpm
resulted in a fuel saving of about 1/4 of what is normally used. I concluded the engines are most fuel efficient with the right load.

3,100 , they live a long happy life. Mine have over 6,000 hours, only turbos changed, aftercoolers cleaned. Do not overprop.
You should be able to spin them up as skiss mentioned.
What air cleaner do you use? Don't pay Volvo's price. Try a NAPA 42473, or 42630 depending on what style you use.