All good advice I see here.
In my opinion the headers are also too small for the engine and the heads. That intake is a pig if someone that knows what they are doing does not do some radiusing in the plenum area, and it should also want an open spacer on it too.
In addition to the cam/compression mismatch I'll bet you are not turning enough rpm for the bigger heads to start coming alive.
If this were a nitrous engine the compression would be fine but the cam wouldn't.
You can try this;
Try opening up your valve lash to the point that is maximum. I am guessing that will be appx .028 and see if it tries to wake up any at all. By the increasing of your valve lash you are effectively killing a little of the cams effective duration. If you get an improvement it is very good evidence the cam is too big in duration for the compression you have. The same applies the other way too. By going smaller on valve lash you can mke the cam think it is bigger than it is just for research.