It is a 4.08 bore and a 4.25 stroke, uses BBC spec rods (Scat), Scat crank, Mahle pistons, Crower solid roller
Just a hot rod.
It lost a bearing when it was a 390 so the uptick in metals is concerning, I'm hoping some pocket of debris that didn't get fully cleaned broke loose... but visible metal is a bit concerning...
Parked for the moment until I have time to do a little investigation.