The 1954 to 1956 Chrysler hemi used the same basic blocks, heads, intake and so on. Both year 392 had different lifter angles, head and block mating surface angles differnt than the 331 nad 354. The 392 also had center sump oil pans, the 354 did not, they had rear sump pans and pickups I beleive the oil pans and pick up are interchangable If you have a 354 you could have the cranksahft offset stroke by offset grinding the rods down to BB Chevy rod journal sizes and use some of the aftermaket H beam rods, that would require a custom set of pistons but the 354 motor would be close to the same size as the 392 and still have thicker cylinder walls than the 392 has. I have ran ran and used of the early size Chrysler Hemi, 331, 354 and a bunch of 392, I believe the 331 had a 3.75 bore, the 354 had a 3.875 bore with the same stroke on both( I can't remember if the stroke was 3.0 or 3.25 or?. The 392 where 4.0 bore with a 3.91 stroke, if I'm remembering correctly still A common practice was to offset weld up the 331 and 354 cranks and then offset grind them back to stock rod size making a welded stroker They held up for a short period of time in the old fueler motors if you used the aftermarket four bolt main caps and didn't overdrive the snot out of the blower Noramlly asperated you should never hurt one of those motors, unless you get it really hot(10 head bolt motor ) detonate it a lot or run it out of oil The early Chrysler Hemi(331-354-392) are a lot better design than the 426 Hemi are