Im new to jet boats but not new to the olds 350/455. I have read everything here about the oiling issues so ive been really careful with my new boat and its BBO. My question is this...when will i experieince a drop in oil pressure? and at what pressure am i not safe? Ive ran the boat as hard as itll go and watched the gauge like a hawk and its never dropped below 40. I dont have my tach hooked up but I can say if the water is smooth ive got my foot all the way down and use the diverter to trim it down right until it stops porpousing...im not saying im trying to blow it but I just cant seem to find the problems that people talk about on the forum?
You said your motor never drops below 40. That's great it's possible you've had some oil restrictions done to the motor. Pushrod restrictors , Cam Bearing restrictors, lifter bore restrictors , head and engine deck modifications and maybe some drain back lines.
If you run it that hard like you say and never noticed any fluctuating oil pressure then your good. Yes that's been said Oldsmobiles don't like to run much over 4900 RPM for long periods.