The 1955 Chysler New Yorker motors where 33 C.I. and made 250 HP with a very small four barrel carb. The first Hemi powered vechicle I bought and owned was a 1933 Ford pickup with that motor in it, swapped the intake out for a dual four barrel off of a Faso Vega(SP?) and scrounged a non matching pair of early AFB I had my Father in Law make a nice set of tubelar headers for it which really help it run Those motor can be made to make decent power with the correct parts and prep, especially a blower I ended up owning quite a few different cars with the early hemis in them, 1957 New Yorker, several Imperials and a 1957 300 hardtop and finally a 1958 300 convertable parts car The 1955 and 1956 Hemi heads flow a lot better than the 1957 and 1958 heads do because of the intake port angle, Chrysler laid the ports over to make better hood clearance in 1957 and 1958 , they alsdo change the lifter bore angles and camshaft designed to work with those changes The hot set up back in the day was to buy a 1956 354 hemi and use those heads, have bigger valves put in the those heads and stroke it using a 1957/58 crank I never did that due to the abundance of the stock parts and my limited budget back then