I have always used Valvoline oil in my cars and Fram oil filters. When I tore any angine apart that I ran valvoline, the lifter gally was clean with no deposits.
I think Castro would be my second choice.
I am sure synthetic oil is better but never used any.
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'82 GT 351W,BBK shorties,
Comp Cam,edelbrock intake
625 cfm carter carb. c-4 tranny w/ pro stick shifter. 4 core radiator
Mallory distributor. 3:27
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