oils ain't oils...
as long as it's a reputible brand, & the engine build was done PROPERLY than it's probably a lifter, (most common cause of any tick from a falcon)
someone stated to use penrite 20W, please shut the fcuk up if you don't know what your talkin about.
oil has 2 grades, cold start & operational temp viscousity. no single grade oil could protect your falcon. or much else to that point.
penrite is good oil.
if anything, without giving my own personal advice, go to autobarn, look in the penrite book, try whats advised for your car, if that doesn't work try a bit thicker. (if your going thicker it helps to use the same manufacturer so you can guage the difference)
maganatec in everyday falcons = not good imo, going off experience.
if your falc is a daily driver than thicker oil or an oil additive might help as a band-aid solution for a few hundred possibly thousand k's.
for a performance engine, it's engineering, not so much engine building > if it's fcuked it's fcuked.
an oversize (thrashed) engine could never possibly compare to a new (rebuilt) engine. it all comes down to tolerances & good engineering practice.
when whas the engine work done ?