Originally Posted by Craig J
Please note that I don't do this for a living...

Me, either, which is why I'm going to follow this thread hoping for those that do to pipe in w/ some feedback.

I am gonna toss out an idea which may or may not have any validity: rod big ends not machined properly, which is causing the bearings to be "pinched" at the mating surface when torqued down. There may be some crank journal fillet interference, too. scope

2021 Challenger 6.4L Scat Pack 1320
100% stock: 1.680, 11.894 at 113.75 (DA 175 ft)
weight reduction, wheels, tires, Hellcat air box: 1.661, 11.686 at 115.97 (DA 710 ft)

1973 Challenger 452 ci street/strip [2008]
pump gas, DOT radials: 1.454, 10.523 at 126.44 (DA 514 ft)