I was told by many Mopar stock and SS racers back in the early 1970s that the 1970 383 two barrel converter was the best choice for a decent stock street and drag strip converter, not the stock street hemi converters
I've tried using a stock 440 motor home converter as a cheap way for better low price Hi Po converter, for street racing, the smaller (11 inch smog converters) later converters work better on foot stalling and having a higher foot stall RPM, around 2800 instead of 2300 to 2500 like the stock 11 inch street hemi converters had