Editing Rebuilding an early Hemi engine (section)
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==Parts interchangeability== Each Chrysler division (Chrysler, Dodge, DeSoto, and Plymouth) produced their own version of the Hemi. Only a few specific parts will interchange, including the following: *All '51-'53 Chrysler front covers will fit all DeSoto engines. *All '56-'58 Chrysler front covers will fit all Dodge engines. *Dodge high block connecting rods may be used in the DeSoto high blocks despite wider side clearance, but DeSoto rods must be narrowed slightly for use in Dodge engines. The lengths are close enough to be compatible: Dodge 6.618", DeSoto 6.625". *Distributors, oil pumps, and bellhousing/starter mounting flange plates will interchange, except for the extended block versions. Keep in mind that these flanges vary in thickness depending on the transmission used. *Valve stem diameter is the same in all engines and length is very close, so the larger diameter valves from the bigger engines can be used to improve the breathing of the smaller motors. Within divisions some parts will also interchange. Although some low block and high block cylinder heads will interchange, care must be taken when considering certain combinations. For example, 392 heads are wider than earlier low block (332-354) heads, allowing the earlier intake manifolds to be used on stock 392’s, However, when using early (low block) manifolds and heads on a 392 block, spacers must be used because the higher deck height of the 392 will align the intake manifold mating surfaces too far apart. Conversely, 392 heads won't work on a low block (331 or 354) Hemi unless a log manifold is used, because the lower deck height of the 331-354 combined with the longer intake runners in the 392 heads will align the intake manifold mating surfaces too close together to use a standard manifold. There are also dowel pin diameter considerations to deal with as well as mismatched coolant passages in the lower corners with some head/block configurations. As an example, ‘56 low block (354) heads will not easily fit on a ‘54 or earlier low block (331) for these very reasons. DeSoto and Dodge heads interchange between high and low blocks without any major difficulty. The differences between the low and high deck heads are combustion chamber, valve, and port sizes. With the DeSoto and Dodge the intake manifold must be matched to the block being used. A low deck manifold is required for a low deck block, and a high deck manifold is required for a high deck block. A cast aluminum 4BBL manifold for the low deck DeSoto has recently been released, and a high deck manifold will follow. Offenhauser has recently re-released a 4BBL manifold for the low deck Dodge. *Hemi heads will fit poly blocks of the same family, but will not fit "A" series poly motors. *Chrysler 331 Hemi heads can be used on the 301 and 331 Polys, and 354 Hemi heads can be used on 354 Polys. *No camshafts will interchange between low and high blocks of any engine family because of differing lifter bore angles. The incorrect cam can be installed, but the engine will run badly. The low deck Dodge early Hemi (241 and 270 CI) will accept a later small block distributor with no modifications. This may also be true of the other Dodges. [[File:331 CID 1951 HEMI BELLHOUSING DETAIL.jpg|200px|thumb|left|331 cid 1951 Hemi bellhousing detail]]
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