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Re: Converting Poly 270 Engine to Hemi (1955 Dodge)??

From: Hank Dozier
Email: dozierhc<at>
Remote Name:
Date: September 14, 2003


Tom.... Most of what has been stated is correct, so I will fillin the blanks. You need to have the hemi head bolts (shorts and long), as these are different. Poly pistons can be used if the cam is stock or at least not high lift aftermarket. If the spare hemi pistons fit, then use them, but the CR needs to be calculated (most were like 7.5:1, some were 8.0:1). Intake manifolds interchange between polys and hemis. Best manifold is 1956 270 poly (biggest ports). Exhaust manifolds are unique for hemis and polys. Rest of the engines are common within displacements (crank, rods, timing chain assys, distributor fitment, etc.). Erik is a good source of information. Be careful, he works for beer and sometimes WITH beer! (Sorry Erik, your past just caught up with you). Good luck with the conversion. I think you will be well satisfied.


Last changed: July 19, 2018