Best NON - Synthetic oil for my motor !!! Give me your advise!

[84LX89GT]

Originally posted by 90'5.0 Conv:
[B]Airate?
B]

When i refer to airating, i mean that because of oil windage (getting sloshed around by the crank OR because of breaking down and turning from oil to a sludge/vapor). I had an '83 zephyr with the oil level in the middle of the full area and i drove it hard for about 5 minutes straight, which should be no problem because i've done that a million times with other cars. Anyways, i heard a knocking and noticed that my 1500 mile old Kendall oil (standard organic) was now black and there was bubbles in it. Coincidentally i had done an oil change on my dad's Chevy truck ('90 2500) and while he was towing going up a small grade, which should be no problem, he noticed that his oil pressure dropped to zero and he heard engine noise. When he looked at the dipstick, his oil was black and there was bubbles.
Now when both of these vehicles were left to cool down and restarted, there were no problems, oil pressure came back up and the oil was in the level area where it's supposed to be. Another thing i noticed about the Kendall oil is that at oil changes (i used that stuff for about 12,000 combined miles for a couple of vehicles) it was ALOT thicker and blacker than other comparable oils.....
...but that's just my experience and what i was referring to when i said airate.
sorry for the long post.