Have some questions about a 5.7 swap into 73 Charger

Since the weight is roughly equivalent to the modern Charger/Challenger I think any converter that works in modern Challenger would work well.

It appears as though the stock Charger/Challenger converter stalls around 2000 RPM, so virtually any converter will do as well as stock. As far as using a slant six converter, I don't see much point considering the huge variety of aftermarket converters available for a 727. Though on a tight budget the looser converter from a slant six might, be worthwhile.

Regards,

Joe Dokes