Chance against a 383 I assume you are talking about. I still have dished pistons in my 360, and my pistons are down the hole a ways, and when I had factory smog heads, and less cam than the E58 police 360, it went 13.3's with 2.94 gears. Only addition was headers and an RPM intake (which the intake really wasn't worth anything to speak of). I think that would be tough for a 383 commando with headers in a Duster with only 2.94 gears. Just say'n.... But you are correct, swap pistons and the 360 becomes a whole new animal.