Although rare, you could get a 455HO in a 70 Judge. Late model year introduction. I agree I don't know why they did'nt put a 12 -bolt under RA IV cars
. A 70 455HO had standard d-port heads (64) and a cast intake. The 71 455 HO had round port heads and an aluminum intake (painted engine color). 4 speed 455 cars in 70 and 71 used the 068 or RA III cam. The 71 455 HO was closer to a RA IV but for performance and a great lumpy idle (527 lift cam) I'll take a IV car all day long.