Since then I have built 3-340s 2 440s, a couple of diesel engines, and some motorcycle engines. Not to mention many BAE hemis.
Does that help any?

I drove my latest 340 at Bonneville at near wide open throttle for over 5 miles at a time with a standard oil pump and it held up fine in 95 degree weather, twice that day with no oil pressure problems. That's a serious workout at wide open throttle for miles at a time.

So,am I killing my combo by running a high volume pump(Melling)on my 383 with a 9 quart pan?
Nearly 90 at startup,and 60 when fully hot.
I have oil restrictors in the heads.
If so,I will order a stock pump tomorrow.
When I put this combo together I had a choice between stock,hi-pressure,or hi volume.
I chose hi-volume based on the info I had at the time,and knowing I had a deep pan.Keep in mind,my car is a street car that i tnt sometimes.However,I always drive it like it's a racecar.