Oil pump question on my future motor

The book by the name how to build big inch Mopar small blocks. On page 40 recommended modifications high-volume oil pump should be used on all high performance LA and Magnum engines. With so many places for oil leaks in this system the high volume pump must be used.
On page 38 Engineers tested the volume of oil flow with a stock oil pump then tested it again with a high-volume oil pump. With the stock pick up the high volume pump did not flow any extra oil.
If you read further on into the into the the chapter you learn that the thin wall tubing pick up flows more oil than the standard pickup. Bubba Bubba blah you guys need to get this book if you don't have it it's how to build big inch Mopar small blocks and covers LA and the magnums.

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