Maybe you can ask comp for a cam with a low ICL short duration and close LDA. Maybe tell us about the engine that is in the truck? Is it low CR?
What tech is telling you is that you need to close the intake valve earlier if the engine is low compression.
The only way I see to get the sound is to buy a cam with a low ICL.the intake center line has a lower number and closes the valve sooner. The choppy idle sound comes from Overlap. thats when both valves are open at the same time(longer than factory)
Its difficult to explain how a cam works,especially for me as Im not as articulate as some of the other guys.
The thumper cams are designed to sound cool more than some other high perf cams.