I'm running almost 108 mph in the 1/4 mile with a smaller cam in my 410 stroked, aerodynamics of a barn door van. I ran a 3.73, then switched to a 4.10 for later mods yet completed (no change in top end mph as of now). I'd say its the tune. Your 60' seems in the ball park. Playing with the carb yielded better times in et/mph in my case.
