The flow characteristics change a lot between oil brands, even with the same viscosities, the chemistry is different also, no chart I know of is very accurate for uses of various oils between brands.
Road racing, street and drag engine are all different things, the oil gets darn hot on some drag engines, oil can be over 250*F by the end of the run. Especially filled blocks.
To determine proper oil weight after some usage I usually use the pressure drop after warmed up, or to much pressure warmed up full throttle, cold pressures to high or low, and heat soaked idle pressure. A racing grade 10w30 will take a lot of abuse.
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