318 driver - cam change or not?

Something I don't see mentioned hardly ever on 318 threads-

We should probably acknowledge that we are dealing with two different groups of engines (actually 3 but group 1 and group 3 could be considered similar)

Group 1 is the 67-70 9.2:1 advertised compression engine

Group 2 is the 71-84 8.8:1 mill

Group 3 is the 85-91 LA roller- back to 9.2:1 and with "302" heads

From all the discussions I read it seems that even that .4 of compression could be a big difference when choosing a small cam for a small displacement engine. Even if it's actually more like 8:1 and 9:1 (I have a suspicion, along with anecdotal evidence that factory ratings got closer to the "true" rating as we get closer to the modern day- IE the LA roller is probably an actual 9.2:1 motor).

We should also probably discuss what the largest lift is on typical 318 heads before milling the valve spring base is necessary.

I don't think you can compare ford 302 performance to 318 performance for a given grind. they are wildly different esp in the head.