This is a pair of original GM cylinder heads for a Big Block Chevy Engine. The casting number on each head is 3873858. These heads are the high performance versions with rectangular intake ports and closed combustion chambers. These heads were used by GM on 1966 L78 396/375HP, 427/425HP, and 427/450HP engines. These heads were also used as a direct replacement for casting numbers 3856208, 3919840, 3904391, and 3964291.
These heads are in awesome condition as shown. There are no breaks are repairs. The externals of the heads are completely stock and look great. The ports and chambers have been very nicely deburred and polished as shown. The guides have been upgraded to accept positive style valve stem seals for better oil control. The heads were surfaced in the past and the deck surfaces look great. These heads just came back from the local machine shop where they were cleaned and magnafluxed to check for cracks. Both heads are crack free and ready to be freshened and installed. These heads should make your engine run like a raped ape!
This is your chance to own awesome factory HI PERF Big Block Chevy heads you have been dreaming about for your special engine or collection at a great price. Don\'t Miss Out!
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