Actually you can figure it out from the numbers, it
may not be perfect like a engine builder than builds
hundreds of engines BUT certain things hold true, a
wide lobe will idle smoother than a narrow one(as in
112 vs 108). A short duration will not rev as high as
a larger duration, and lift is based on the heads
abilities (300cfm @ 600). So if you look at the head
flow and your other parts you can figure out the cam.
So for instance you have a good bottom end that can
rev you will want a good duration, the heads flow
good at 600(now you need to figure lash, deflection
and angle of pushrods, if any for losses) and in
this case we will say its a SB so at about .050 over
the head flow. You wanted a good idle thats a wider
lobe, we will say 112, but with the 112 you have
low compression low in the revs so you can add compression.
This is just a quick and simple