|
By slick56 - 11 Years Ago
|
Just lifted my heads on my Y, chasing low compression on 1 cylinder, and find that although i have the ECZ-G heads, one has the small part no., and the other, large.
I seem to recall that the large part no. heads were posted, and the small ones were not.
Is that the only difference, eg. compression ratio's, etc.?
Neither head has the "steam" holes, is this worth doing?
Tia, Al.
|
|
By Oldmics - 11 Years Ago
|
Have not heard about the difference in font casting sizes being an indicator of posted heads or not.
I have heads with both casting font sizes that are posted and also not posted.
The large lettered heads are always installed on T Birds.
The heads were cast at two different factory locations.Its more about a date of when the heads were cast.The later dates were the posted heads.
Oldmics
|
|
By slick56 - 11 Years Ago
|
Thanks Oldmics, neither of the heads are posted.
Are there any other differences, being they were cast in different foundries?
Where do i find the dates of manufacture?
There was an excellent picture article on here by a member who posted his heads,
been looking for ages but can't find it, will save in favorites when i do.
Also researched the steam hole issue on here, will not bother.
.
|
|
By NoShortcuts - 11 Years Ago
|
My understanding is that none of the small font 'G' letter heads were posted.
As Oldmics indicated, the large letter 'G' heads may be 'posted' or 'un-posted' depending upon when they were cast. John Mummert's web site indicates that pre-May of 1957 'G' heads were un-posted. Sooo... there were a lot of 1957 Fords and Mercurys likely assembled with un-posted heads. '58 Mercury's with y-blocks are a good source for posted 'G' heads. 
In my work with the two series of heads (small 'G' and large 'G'), the combustion chambers appear to be identical. That said, my comparison of the intake and exhaust porting indicates that different sand cores were used in casting the two series of heads! Both the intake sand cores and the exhaust sand cores were different in the small letter 'G' heads. The striking difference to me is the shape of the bowl area under the intake valve and the port area closest to the exhaust manifold.
Other than 'posts', I've observed no other differences in large letter posted or un-posted 'G' heads.
Based upon information shared on this 'Forum', I also am not adding 'steam' holes to y-block cylinder heads or engine blocks that do not already have them.
What I don't know about casting date codes would fill a book.
|
|
By mctim64 - 11 Years Ago
|
The small letters are cast in Dearborn and non-posted, the large are Cleveland and can be either way. Best way to check is stick your finger in the hole and feel for the post. Both have the same volume combustion chambers.
Ted Eaton photo
|
|
By NoShortcuts - 11 Years Ago
|
Your pictures are great, slick56. Sometimes my computer shows pictures in Forum threads, and sometimes it does not. I went back to re-read your question, and the pictures were there that I did not see previously of the cylinder head casting letters! 
Clarification (because your pictures didn't look that different when I looked at them  )...
1) small letter 'G' cylinder heads have casting letters 1/4 inch in height
2) large letter 'G' cylinder heads have casting letters 3/8 inch in height
3) notice, too, that the casting letters are oriented in different directions on the two heads in relation to the intake manifold mounting surface.
|
|
By NoShortcuts - 11 Years Ago
|
|
slick56 (10/20/2013)
...There was an excellent picture article on here by a member who posted his heads,been looking for ages but can't find it, will save in favorites when I do.
Ted Eaton put this up on 5-16-2013 when someone else was looking for 'head posting info.'
__________________________
Here’s the link to the ‘how to’ pictorial. http://forums.y-blocksforever.com/Topic47592.aspx I've also gone through some of those other threads and fixed the links within them so they will function again.
And here's another link. http://forums.y-blocksforever.com/FindPost57138.aspx
__________________________
I think the first link is the step-by-step detailed procedure that you're looking for. The second thread has some other good pertinent info though, also.
ADDENDUM: I JUST TRIED TOGGLING THE ABOVE LINKS, DID GET TO THE CORRECT PLACES, BUT NO PICTURES! PERHAPS THIS IS RELATED TO MY COPYING AND PASTING THE INFORMATION???
|
|
By charliemccraney - 11 Years Ago
|
|
NoShortcuts (10/20/2013)
ADDENDUM: I JUST TRIED TOGGLING THE ABOVE LINKS, DID GET TO THE CORRECT PLACES, BUT NO PICTURES! PERHAPS THIS IS RELATED TO MY COPYING AND PASTING THE INFORMATION???
It seems to be working correctly.
|
|
By slick56 - 11 Years Ago
|
I think the first link is the step-by-step detailed procedure that you're looking for. The second thread has some other good pertinent info though, also.
ADDENDUM: I JUST TRIED TOGGLING THE ABOVE LINKS, DID GET TO THE CORRECT PLACES, BUT NO PICTURES! PERHAPS THIS IS RELATED TO MY COPYING AND PASTING THE INFORMATION???
Yes, the link is working fine, pics are a-ok.
That is the article i was looking for, thanks heaps
.
|
|
By Y block Billy - 11 Years Ago
|
|
I dont think you have to worry about posting them unless you plan on supercharging!
|
|
By slick56 - 11 Years Ago
|
If, as aussiebill suggests, the blocks under the centre spark plugs are 1.000" before machining,my heads have been milled .025".
I figured the posts will give a bit more support.
Thoughts?
.
|
|
By NoShortcuts - 11 Years Ago
|
|
Y block Billy (10/21/2013)
I dont think you have to worry about posting them unless you plan on supercharging!
Give consideration to what Bill has suggested. A large number of '57 Fords and Mercurys were produced with un-posted heads and never had trouble with head failure.
Yes, your engine has been overbored .060 and your heads milled .025 all of which increases the compression ratio. Using today's thicker composite head gaskets, you likely have brought everything back to where it was new from the factory. 
My understanding is that Ford moved to employing the steel posts within ALMOST all of their late '57 head casting series after having problems with heads used on the '57 supercharged 312 engines in competition use. -Truth be told, likely those with supercharged heads having failure had figured out ways to increase the factory limited maximum boost from 6 psi to something higher. 
Unless you move to domed pistons, a supercharger, or turbocharger, posting the heads is something you likely don't have to spend time doing.
Food for thought.
|
|
By PF Arcand - 11 Years Ago
|
|
This posted head information seems to be getting confused? Are we given to understand that "G" heads were used by Ford on supercharged engines?! That isn't my understanding. According to the Reese/Mummert chart, SC heads were originally EDB-D, E & C heads. ECZ-G heads were standard on "E" code engines, not "F" code engines.. Correct? Further, Ted Eaton says that the factory specified that early "G" head should only be milled up to 0.010" Ted says it's alright up to 0.025," providing that other changes to increase compression, such as domed pistons, have not been done..
|
|
By NoShortcuts - 11 Years Ago
|
|
PF Arcand (10/22/2013)
This posted head information seems to be getting confused? Are we given to understand that "G" heads were used by Ford on supercharged engines?! That isn't my understanding. According to the Reese/Mummert chart, SC heads were originally EDB-D, E & C heads. ECZ-G heads were standard on "E" code engines, not "F" code engines.. Correct? Further, Ted Eaton says that the factory specified that early "G" head should only be milled up to 0.010" Ted says it's alright up to 0.025," providing that other changes to increase compression, such as domed pistons, have not been done..
Hmmm... Thanks for writing, Paul. Apparently, my thread entry information wasn't clear as I stated it.
My understanding is that early production line 1957 supercharged engines were assembled with heads having the casting letters EDB-D. Some problems were encountered in competition with the roof of the EBD-D combustion chamber 'lifting' due to increased compression pressures. Ford responded by adding steel rods to the internal design of the head casting. Cylinder heads with the casting letters EDB-E (heads with the steel rods that we call 'posts') became the production line replacement for the earlier EDB-D cylinder head on the supercharged engines. As you noted, John Mummert's chart indicates that there is indication of some factory supercharger heads with the stamped letters EDB-C.
The addition of the steel rods in the casting of supercharged y-block cylinder heads was subsequently incorporated in the making of ALMOST all other y-block cylinder heads that Ford was producing during the remainder of the 1957 model year.
The only exception to the later use of steel posts in the making of y-block heads during the '57 model year was the Dearborn produced small letter ECZ-G cylinder heads mentioned earlier in this thread. This has been indicated to me by J.M. and stated by Tim.
___________________
Regarding '57 ECZ-G cylinder head applications:
Per John's cylinder head chart, in model year '57, cylinder heads with the casting letters ECZ-G were used in assembling Ford 272, 292, and 312 un-supercharged engines for passenger cars and many 272 truck applications.
312 'E' code dual quad equipped engines had ECZ-G cylinder heads.
All 1957 Thunderbirds (even those produced into December of 1957), with 'C' code 292 engines and 'D' or 'E' code 312 engines used the large letter ECZ-G cylinder heads.
I have never seen small letter ECZ-G cylinder heads on any '57 or '58 Mercurys.
John Mummert's cylinder head chart lists specialized 1957 production year y-block applications (HD trucks, industrial engines) that may also have the steel posts depending upon when the heads were made. These include heads with the casting letters ECR-(various suffixes) and ECZ-A.
___________________
Regarding the milling of ECZ-G heads... I agree with removing as little material as possible when reconditioning them. A look at the thickness of the surface that mates with the block any place that there's a cooling system opening clearly shows that there is not that much cast iron material there to begin with.
___________________
I hope this clears up any confusion I generated.
Regards,
|
|
By pegleg - 11 Years Ago
|
|
Charlie, the steel posts are actually simply an added iron post in the casting. The were not really steel but part of the actual cast iron casting, not a separate piece.
|
|
By NoShortcuts - 11 Years Ago
|
|
pegleg (10/22/2013)
Charlie, the steel posts are actually simply an added iron post in the casting. The were not really steel but part of the actual cast iron casting, not a separate piece.
THANKS, Frank. I've never cut a head open. Eickman's book was my source. Like any book, we know that there are a few errors in it.
Charlie Brown is still learnin'!
|
|
By slick56 - 11 Years Ago
|
|
pegleg (10/22/2013)
Charlie, the steel posts are actually simply an added iron post in the casting. The were not really steel but part of the actual cast iron casting, not a separate piece.
Picture of the post, courtesy of Ted in a previous "post".
.
|
|
By NoShortcuts - 11 Years Ago
|
|
Excellent! Hadn't seen it before. Kudos
|