I believe this is a hotter version of the stock 340 cam. The stock cam is 268/276 advertised, 210/220 @.050", 429/444 lift, 114 lsa IIRC.
The P4041998AE specs at 268/276 advertised, 228/235 @.050", 429/444 lift, 114 lsa.
The '68 manual trans cam is different.