I am repling to you about the cam you want to use in your 390 build. I have a 79 ford 4x4 and it had a 400m in it but I did not like it so I rebuilt a 390 and put in it. I put a cam in it with to much lift and all I do now is bend push rods and a friend told me that on FE heads you must have the push rod ports inlarged to give them room for a higher lift cam.