318 la / mag

Magnum block will have hydraulic a roller cam.
Yeah I don’t know what that is or how to tell unless removing it from the car . How to tell if my heads are magnum ? Cause I wanted to use them on another LA motor . This was spare motor I got . I don’t want to pull entire motor out of my car . I wanted to put hood heads from this motor as I k ow it ran and seemed to run pretty well last year