All engines are built as both hemispherical and polyspheric (except as noted)
DeSoto (no polys): 276, 291, 330, 341, 345
Dodge: 241, 259 (poly only), 270, 315, 325
Chrysler: 301 (poly only), 331, 354, 392 (hemi only)
The only cross-brand exceptions I know of:
Dodge D500 354
DeSoto mid-price used Dodge-based poly motors
1955 Plymouth used Dodge-based poly motors
