.050 duration on a 484 is ~241, the 474 is around 232, IIRC.
for a heavy car and highway gears, I'd keep .050 duration ~224@.050 max, otherwise you'll be disappointed with idle-3500 RPM performance.
1976 Spinnaker White Plymouth Duster, /6 A833OD 1986 Silver/Twilight Blue Chrysler 5th Ave HotRod **SOLD!*** 2011 Toxic Orange Dodge Charger R/T 2017 Grand Cherokee Overland 2014 Jeep Cherokee Latitude (holy crap, my daughter is driving)