Basic Magnum question: Safe maximum RPM on stock internals?

Thanks for the input, guys!
The stock cam is pretty mild. I don't know the specs off hand but I gather that it's the same as whatever Chrysler used in the Ram/Dak/Grand Cherokee versions. The idle is very mild. The power dropping off after 4,500 sounds likely.

I have a M2 dual plane intake, 650 cfm carb, 2600 RPM TCI stall, Doug's headers...but the motor feels pretty lazy everywhere.

I have no idea what kind of care the motor had before it fell into my hands. The seller claimed that only had a "couple thousand" miles on it but it sat a lot...and there is a slight/occasional lifter tick that I will have to tend to.