I still go w/ the old school train of thought b/c it's served me well. I use 20w50 in my hemi b/c the clearances are on the loose side. Same w/ my 440.
My BB chevy is a little tighter, so it gets 10w30.
All using Valvoline VR1 conventional race oil.

CHIP
'70 hemicuda, 575" Hemi, 727, Dana 60
'69 road runner, 440-6, 18 spline 4 speed, Dana 60
'71 Demon, 340, low gear 904, 8.75
'73 Chrysler New Yorker, 440, 727, 8.75
'90 Chevy 454SS Silverado, 476" BBC, TH400, 14 bolt
'06 GMC 2500HD LBZ Duramax