Boss 351 cylinder head info....

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KenMt

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Have 351 boss heads.
Hello.I have a set of 351 Cleveland 4 bbl heads that I need to identify.The casting # is D1ZE.They have pushrod guideplates and screw in rocker arm studs.They still have Ford script valves and the ports etc are unmolested.According to several websites,it sounds like I might have a set of 1971 Boss 351 heads,but not sure.I am going to sell them and am looking for any advice as to their worth.They currently have surface rust..If they're worth much I will probably beadblast and have them magnafluxed,although they came off a running motor.[Yeah,a 2V short block]

 
71 Boss 351 heads carry the D1AE-GA casting number

71-72 351CJ are D1ZE-DA

Boss heads should also have single groove valve keepers and closed chambers. The 351CJ will have the 4 groove keeper and open chambers.

No matter what, toss the Ford valves as far from a running engine as possible, since they have a nasty habit of losing a head at high rpms and destroying the engine.
 
Boss 351C heads are D1ZE-B, the two other heads with the same basic number are D1ZE-DA and D1ZE-GA. You'll also need to get the alpha suffix. If they are -DA or -GA heads you'll also need to get the date codes to identify what you have.

 
Yes under one of the two middle intake ports there is a D1Ze cast in.Under the other middle intake port there is a larger DA underlined.The only other casting mark i found was a circle marked 1 3 5 7 9.[besides a couple of "4"s with a dot and a F inside a circle.]The pushrod guideplates have a Ford C9 part # stamped on them.Sounds like I have a set of 351 CJ heads which arent that rare or desireable according to some of the 'net Cleveland gurus. I dumped myself,the hand cart and the head in a snowbank bringing it into the shop so I will let it and me dry and give it a better look over tomorrow.Thanks a bunch guys for the quick responses. ken

 
Yes, they are CJ heads, but at least have the large valves. Not as desirable as the Boss or closed chamber heads, but still can make a lot of power. They are also good for stroked engines for keeping the compression ratio under control. Already having adjustable valves is also a plus, not cheap getting them machined.

 
For the future ...................much easier to start with the DATE CODE ! OEM Boss Heads have a very short run range OK4 to 1E7 (for the close chamber)

Mark

P.S. So SO MANY 1970 heads were "converted to studs" as a performance mod (from racing to the street) that DATE CODES are the best way to know if you have a $4000 set or a 400 hundred dollar set

 
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