360 TrueStreet Magnum Build

Sweet engine on a budget.
If you put a smaller cam in the same engine, for a truck that just was used for towing, max rpm 4000 what would you expect for torque?
Say for instance a cam that would pull clean from 500 rpm to 3500.

I wouldn't expect anymore torque to show up--I would just expect it to be shifted lower in the RPM's. A slower more conservative timing curve may be required though. J.Rob