Ok , need to step back

if it ain't broke....... that Dart sounds like a badass car and there's a cool factor with that bored and stroked 400... you know what to do, cut your losses and put the Duster up for sale with the 340, chalk it up to an experiment you shouldn't have attempted.. recoup some bucks and move on. ...or you can spend another year working on it. :BangHead: JMHO.

Hell He USED to have an early hemi in the thing!!

Richard, I'm not sure a 400hp SB is gonna be much of a mileage / cruiser improvement over a mild 400 stroker!!!