From a previous thread I posted Skidmarkjunkies(a really sweet person by the way)said that a putting a 390 crank in a 331 makes a 412 caddy motor but he wasnt sure so I was wander if any one knew if this was true and how hard it was and what was needed because I believe that would be one mean motor and the cars called the junkyard kid so the more pieced together the better but still keeping it safe
the stroke is longer for a 390,but you'd still have to bore the 331 by 3/16ths just to get it back up to 390.
The Jalopy Journal
