[matt68gto]

I am wondering what heads I have on my gto. The car does not have orignal motor and the guy I bought it from did not have any clue.
dn E158 38
dn E138 36
these are the numbers i could make out. the casting seemed to be different on both sides, or it was hard to make out the stamp of the casting.
thanks matt

 

[05GTO]

I am wondering what heads I have on my gto. The car does not have orignal motor and the guy I bought it from did not have any clue.
dn E158 38
dn E138 36
these are the numbers i could make out. the casting seemed to be different on both sides, or it was hard to make out the stamp of the casting.
thanks matt

I believe E138 and E158 are date codes for May 13 & 15, 1968.

Here are pontiac head codes;

http://www.boyleworks.com/ta400/psp/heads.html

 

[lars]

Pontiac head ID codes are cast into the heads on top of the 2 center exhaust ports. E158 is a date code from either 1968 or 1978. The head ID from the late '70s will be a 6X or 4X code, most likely. From 68, the code will likely be something like a 16 or a 62. Get the code off the exhaust ports and I can tell you exactly what you have.

 

[matt68gto]

thanks for fast response.
the code is 16 or possibly 18, its hard to make out the 6 or 8.
I would have to lean towards 16
matt

 

[lars]

Most likely, you have the casting number 16 heads (casting 18 would not be a performance head - you might want to check it closely). The #16's are very good heads, and were used on 4-barrel GTO, Grand Prix and Firebird 400 & 428 applications in '69. They have 72 cc chambers, large valves and pushrod guideplates. GTO applications for these heads were 350-horse 400 (standard engine) and Ram Air III with auto trans (manual trans RAIII had the "real" #48 RAIII heads).