I drive a 75 Duster 360 w/ #'s engine and rebuilt w/ Badger Flat Tops, 340 Resto Grind Cam, 1970 340 intake and 1.88 J Heads infront of a built 727 and a 3.21 8.25 sure grip.
The car runs extremely rich, is not very tunable to me (but thats me w/ 0 knowledge of carbs) and gets about 9-11 MPG...