318 LA rebuild after losing a valve seat

checking with the lifter bottomed out?
*
do you have any old lifters
take two apart and fill with solid with washers or whatever and retest intake and exhaust
or use a solid lifter (which may have a different seat height)
in fact you have to check and see if your new lifters have the same seat height as your old or stock lifters
all lifter heights changed around 1967 for example and the pushrod ball size changed too
DO NOT USE THE early lifter pushrod combination eventhough parts catalogs still show them
replace both
there are good reasons Ms Mopar upgraded