If your going to get a block(6.4, Hellcat) go 426, 4.05 stroke with the 4.09 bore, and don't look back. As for cam inertiamotorsports.com tell these guys what your looking to do and they'll help you with a good tow haul cam.

I have 426CI 6.4 with Eagle heads in my 2014 ram right now, , pulls like a V-10 , gobs of low end break stuff type pull.
I had 392 with eagles and a SRT 392 Auto cam in it, ran great but no bottom end, the cam didn't like that off idle pull, even with the stock Eagle intake.

Truth has no agenda, but those with an agenda make their own truth.
Some of us are so open minded they only see their View