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Yes, NO, Maybe

From: Mike Patterson
Date: February 19, 2001
Time: 07:47:15


Mostly it depends on what your working on. Up until 1958, Chrysler, Dodge, Desoto and PLymouth each had their own unique engines, with Plymouth being the make not having an available Hemi. The MOPAR Preformance book lists a total of 14 early Hemis (4 for Chrysler, and 5 each for Dodge and Desoto). It also goes on to indicate that all were available in either a Poly version or Hemi version. Several of the articles I have come across and information in interchance manuals indicate that the only major diffrence between the Hemis and polys are the heads (including valve train), valve covers, Intake and exhaust manifolds. In other words turning a poly into a Hemi is a bolt on BUT ONLY WITHIN A SPECIFIC MAKE. HEMI HEADS DO NOT INTERCHANGE BETWEEN THE MAKES (CHRYSLER HEADS WILL NOT FIT DODGE OR DESOTO< DODGE WILL NOT FIT CHRYSLER OR DESOTO ETC) I.E. If you have a 315/325 Dodge poly car you can turn it into a D500, by simply bolting on the 315/325 Hemi heads and associated parts the same would hold true if you have an old 354 Spitfire (poly Chrysler) and want to turn it into a Hemi Simply find a set of appropriate 331/354 heads and associated parts. If you've got a Plymouth motor your likely SOL as no Hemi versions were avaialble for these engines. On the bright side if you are working on a Plymouth, and come across a complete Hemi, It's pretty much a bolt in swap. A site for more information is Hope this helps.


Last changed: July 19, 2018