oil pressure
 

100% correct. I use to worry all the time because I had the same problems before and after engine upgrades. I would always be looking at the pressure and it would concern me. Never ever had a failure. I just got engine temp gauges and monitored them along with the pressure. If it continues to be the same and reliable with said pressures, leave it alone and run it and have fun. Your stock pump is fine. GM has been making them for years. If you do pull the engine just check your clearances between the gears and pump cover. You can always bump up the pressure by reducing the clearance between the gears and your cover to near .0025. You reduce this by sanding (300 grit) your housing on a very flat rigid surface, very little at a time and keep checking. Be sure and check your gears and inside the housing for signs of wear. If there are then replace it with a new hi volume/pressure pump. Even with a new pump it is always a good idea to open it up and check it out as mentioned above.

Maybe it just needs a bigger oil cooler. Sounds like you are getting hot oil, and hot oil is thin oil, and thin oil is low pressure.

OK,
I came here with a Similar Problem. Had a 90 454 Mag that was installed in a 2001 Hawaiian 24 ft. The Motor rotted apart from poor Maintenance in Salt water. Replaced motor with a fresh rebuilt short Block done locally. I had them build it for a Boat and Balanced. Installed a Hipo Melling pump.
Fired it up at 40 lbs cold and idle. Stays at 40 warm then drops to 25-30 at 2-4000 rpm. Cools down and back to 40 at idle or 4000 rpm?
Pulled sending unit and tested with Air Compressor at various pressures. They Match the Gauge pressure. The Oil filter Block mount has 2 port above it. 1-is an 1/8" NPT the 2nd is a 1/4" NPT that is more center with the Filter base. Dose it matter which port is used?
I'm using 10-30 Synthetic. 2 hours on the Motor.
Not sure about the Bypass valve for the Cooler/Remote filter installed?
Not sure what Gen the Block is. How would I find out?
Any Ideas?
Ron

Yes it matters which port u use ,,but i could not tell u which is which !
But if u hook them up the wrong way your oil does not run thru the filter correct .:eek:

Well the Lines are right. What I was not sure was the Oil Sender Ports. The 1/8" NPT was left of center and the 1/4" NPT was center with the Filter Mount base. Both are about 2" above the Filter base mount..
Now for the Filter, it is not the Mercury Filter. It's a short Bosch. Plugging in a Manual gauge in the Morning in to the 1/4" to see if?
Ron

Ron I think you may want to go to a thicker oil. I run 20-50 in mine. Have you guys both checked to make sure that you have the correct amount of oil in the motors? You could be over full and airating your oil as well. My 420hp 454's are currently idling at about 500 rpm and I some times freek when I look at the oil preasure forgetting how low they idle. If I bump them up to about 800rpm they are at 10-15psi when warm.

When I first Poured the Oil in, I had 7 Quarts in. Fired it up, timed it, checked all the leaks:eek: Pulled the stick and its full. From what I can tell it looks like the Mercuiser 8 Qrt pan. It had a Windage tray and I had to get a Milidon deep Pickup. Here in the Driveway it will show 40 lbs at all RPMs. I then took it to the Lake for a Shakedown. It did the exact same thing as the Old Motor did. Warmed up and then the Pressure dropped to 25 lbs at 3-4000 rpms. I'm using 10-30w Tech 100% Synthetic oil from Wallyworld as I know it's good stuff.
I ran my Sandcar for 3 miles in the Dunes@ 5-7000 rpms with no Oil! No damages. So I was sold for sure! I will also pick the Builder's Brain along with the Other OffShore Racers I know here.
Ron

Well I finally feel better now!
I installed the Manual Gauge on the Motor in the 3/8" npt port. I also removed the Mobile 1 Filter and took Smitty's suggestion and installed the K & N HP-3002 Filter. Fired it up and there is was! 50 lbs cold. Warmed it up and it hit 60 lbs @ 4000. Idled @ 40 lbs and 140 degrees water temp. Will take it to the lake in a couple of days for another Shake down.
Thanks Guys,
Ron:drink:

now I run between 10-20 psi at 3200 rpm, engine hot.

Now that 10-20 lbs at cruising would just make me worry that I may not make it back and ruin my day! :eek:
Change your filter to the K & N HP-3002 and see how that works out fer ya.
How many hours on the motor? Remote Filter?
Ron