Sounds like a good combo, 3.91 gears will really help and get the cam degreed so that is ruled out. Intake should help the 60 times and not lose much on top end. What is your fuel system? What size line?
My old 68 GTS 340 with stock X heads with 273 rockers and a smaller MP solid cam, 235 @ 50 and around .480 lift. degreed and advanced 4 degrees, 3800 stall 727, air gap intake, 4.10 rear with 26 inch drag radial, 750 DP holley carb. It took 20 degrees initial all in by 2200. Its was a little lazy off the line and ran close to what yours is running until I went to an electric fuel pump and regulator, it already had 3/8 fuel line. Got it down to 12.80's @ 105 in good air.