My question would be do you plan to make any other changes if you do this ? I only ask because just the stroking from 451 to 470 may not pick it up much without any other work. You will be picking up 19 cubes but without other mods I dont see that picking you up more then a tenth or two. I would want to do other work at the same time like maybe some head porting if yours dont have much done to them. Or like Greg says and just go real big and with other work pick up alot ! I know I went from a 906 headed 440 to an EZ headed 493 and I also went with a little more cam also (MP.557 to a .585 & .592 with 264 & 270 @ .050). I did keep the same 850 carb and same gear and converter and I went from 11.49 @ 116 to 10.76 @ 124.79. But I did a little more then just adding the cubes. Ron