Could be, could be. The Duster is a little lighter than a Dak with less frontal area and the Enginequest heads flow a lot better then stock.
While not a race converter it is a 904 converter for a 318 application and I can blaze the tires for a block if I load the 5.9 against it for a millisecond.
I'll have to hook up a tach and see what it flashes too.
This winter the car is slated to get an overdrive trans, either a 44RH or a A-518 (904 or 727 with overdrive) and was going to purchase a good converter then.
Don't have to worry about slippage much on the highway with lockup and overdrive