I am shopping comp cams for a package and what I want is for 68 and up. If I want to run it in my 67 block I have to machine the lifter area ? I am getting the kit with valve springs also. COMP Cams CL21-306-4. Has anyone done this before ?

 

Here are the factory 440 cam specs for a 68 Charger/Coronet

Intake opens (Before top center) without Power Pack 18 deg/with Power Pack 21deg
exhaust closes(after bottom center) 58 deg 67 deg
exhaust opens (before bottom center) 66 79
exhaust closes (after top center) 14 25
valve overlap 32 46
intake duration 256 268
exhaust valve duration 260 284
valve lift intake .425 .450
valve lift exhaust .435 .458
the low no is a mild 440, the high no is the HP 440
the cam you are looking at is a little more lift ect. i think it should fit with no mods. my ideas is i would not use a bigger cam than the one you are looking at as a daily driver. check out ZDDPlus to get zinc for can breakin DO follow the instructions from the cam mfg. do check the spring retainer to valve guide clearance.