Cams for Dummies ??

Problem is there's no rule of thumb or calculations that can guide you even DV's 128 only calculates LSA, lift is a fairly easy spec to figure out but the rest like duration you kind have to know how it gonna react to mainly Cylinder heads and Displacement.

Heads are the main NA HP component, generally a race cam and CR can get 2-2.5 hp per cfm, a street strip type cam like 230-250 with 10.5:1 cr gonna in the 1.7-1.9+ hp per cfm and engines with less cam and CR will just be lower hp per cfm. Obviously there's more to it then cam and CR to hit these numbers the rest of the combo has to match especially closer to max effort 2.5 hp per cfm.

Then you got how displacement comes into all of this plus how well you fill that displacement Volumetric efficiency (VE%). To make X hp take a certain amount of fuel and air in a fairly narrow range, so an engine to displace say 2 hp per cfm is gonna take certain amount of revolutions depending on cid and ve% and ve and other efficiency vary with rpm why torque curve ain't flat.

Eg. You want peak power with a 340 around 6000 rpm stock head vs trick flow is gonna be two different cams, the trick flow should need less cam to get there. But alternatively say you want peak power at 6000 rpm for both a 340 and 440 the cams could vary similar depending on the heads etc.. on each.