Ford recommends 0W-20 for the Coyote motor (except for some of the track package option cars) so you probably do need to use a thinner
oil. The old (ancient) rule of thumb is a minimum of 10 psi of
oil pressure for every multiple of 1000 rpms. Since these are 7,000 rpm redline motors in stock trim, you are looking for at least 70 psi plus, when reving it up.