Seems to me you're working blind trying to choose a camshaft without knowing all the parameters of your build including port volume and head flow. How many camshafts do you want to buy using the trial and error method? Getting all or as much information possible before you start switching out camshafts is paramount. Info such as: bore; stroke; piston dish/dome; piston type/weight/design; deck clearance; compression ratio; rod length; rocker type/ratio; valve size; chamber volume/shape; head heat; CID; intake type, runner length/dia; port volume/length/average diameter; header primary length/dia; muffler type; tail pipe dia; carburetor or fuel injection type and size; intended use. Once you obtain the info choosing a camshaft is simpler.
Myth or not I believe charge velocity is the important point when buying and/or porting heads. The more air an engine uses the more power it can produce. Porting a set of heads for large cc values will result in the potential for more airflow but if the same porting results in slower flow performance will drop at lower rpm. If an engine can use X cfm of air at any rpm that's all it will use even if the heads can supply 2X cfm. Volumetric efficiency is maintained by good air velocity. If you have good flowing heads supplying all the air the engine needs then increase the port size, while leaving the rest of the engine the same, the larger volume port will result in a slower moving charge. Bigger isn't always better. Heads are ported to the needs of a particular engine, not all engines are the same and heads ported for one engine may not necessarily work on a second engine with different specs.
Then there's always the fear, and I hope not, that the person who ported your heads screwed them up royally. Anyone can buy a die grinder and have at a set of heads, that doesn't mean he/she knows what they're doing. I have grinders and have ported a few but Dave has ported an untold amount of heads and has developed CNC programs for Pontiac heads and aluminium aftermarket heads, there's no way I would have done as good a job as he did, so it was worth the money. I'm sure you will get yours working well once you find out what was done to them and get the corresponding camshaft.
Back to Glider's question, The aluminium heads may be what you need for your detonation problems. As Ordy and Bronze bird say, phone them and discuss what you have and what you want, I'm sure they will lead you in the correct direction. Just remember they boast some pretty good numbers for out of the box performance but they are not on a stock engine and you are probably wanting some street manners not just the highest HP number you can obtain. High HP numbers on the dyno are nice but you still have to drive your car on the street, unless your's is for drag racing only.
