From what I understand is the regular 5.7 Charger and the Challenger have a limit of 120 mph stock. Of course that can be tuned out as well. I think the Hellcat models have a higher limit around 150 mph.
Think the demon is limited around 160 and trackhawk is around 180, but that’s about as fast as anyone has got a trackhawk going stock anyway (drag limited). I’m not sure the hellcat is limited, but it might be in the same range as the demon. Both the demon and the hellcat must be easily bypassed though as there’s tons of data showing them over 200+ stock.