Disappointed in my 383 on the Dyno

I was told it is a hydraulic roller cam from edlebrock to go with the top end performer rpm kit. The shop i had it at yesterday that did the dyno tuning said its a very mild cam. I know it would be better if i knew the specs of the cam but without tearing it apart, giving you guys what i know is all i can do.
Can you run a compression test and tell us what the cranking rpm cylinder pressures are. This will give us a good idea of the engines potential.