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Re: 440 head gaskets
[Re: 68CoronetRT]
#1049853
08/16/11 10:42 AM
08/16/11 10:42 AM
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Joined: Jan 2003
Posts: 74,978
U.S.S.A.
JohnRR
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Quote:
78 cc on the combustion chambers which I believe means they were only cleaned up not milled. Mopar Muscle article says the 915 heads were 78.5 cc stock. My stock 906s were about 88 cc IIRC.
The mopar muscle article is WRONG , The 915's I have are 81ccand the few sets of never cut 906's I have done or had done have never been less than 90 cc , some as high as 92cc.
Get a pair of dial calipers and measure the thickness of the head bolt boss under the exhaust ports this will give you an idea how much they have been cut, factory heads seems to be 1.000 .
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Re: 440 head gaskets
[Re: JohnRR]
#1049857
08/18/11 02:21 PM
08/18/11 02:21 PM
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Joined: Aug 2004
Posts: 1,047
Arizona
68CoronetRT
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Arizona
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Quote:
Quote:
78 cc on the combustion chambers which I believe means they were only cleaned up not milled. Mopar Muscle article says the 915 heads were 78.5 cc stock. My stock 906s were about 88 cc IIRC.
The mopar muscle article is WRONG , The 915's I have are 81ccand the few sets of never cut 906's I have done or had done have never been less than 90 cc , some as high as 92cc.
Get a pair of dial calipers and measure the thickness of the head bolt boss under the exhaust ports this will give you an idea how much they have been cut, factory heads seems to be 1.000 .
Boss measures 1.000 - 1.003"
When CCing a chamber do you try to keep the fluid level to the head surface or allow it to "baloon" upward?
With the heads perfectly level I filled the chambers so the water did not extend above the head surface - this gave me the 78 measurement. If I allowed it to protrude above the head surface but not break over the edge of the chamber it was closer to 81 CCs.
I would think it needs to stay level with the surface myself but not sure about correct procedure.
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Re: 440 head gaskets
[Re: marvo451]
#1049859
08/20/11 09:10 AM
08/20/11 09:10 AM
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Joined: Jan 2003
Posts: 74,978
U.S.S.A.
JohnRR
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Quote:
You need a piece of plexiglas greased and sealed to the head surface. Drill a small hole in the plexiglas and fill until the chamber is just full and all air has escaped. Tilting the head some helps accomplish this.
78cc with a 1.000 reading , that's interesting...
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Re: 440 head gaskets
[Re: marvo451]
#1049860
08/20/11 10:39 AM
08/20/11 10:39 AM
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Joined: Aug 2004
Posts: 1,047
Arizona
68CoronetRT
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Quote:
You need a piece of plexiglas greased and sealed to the head surface. Drill a small hole in the plexiglas and fill until the chamber is just full and all air has escaped. Tilting the head some helps accomplish this.
When I get a chance I'll try it this way.
Thanks.
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Re: 440 head gaskets
[Re: 68CoronetRT]
#1049861
08/20/11 10:47 AM
08/20/11 10:47 AM
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Joined: Aug 2006
Posts: 614
Michigan
Get-X
mopar
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mopar
Joined: Aug 2006
Posts: 614
Michigan
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It will vary a lot depending on the valve job and the valve head. Put a set of valves in that have a flat head replacing the OE dished head valves and you'll see different cc values.
'65 Belvedere
'68 GTX
'57 Dodge pickup
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Re: 440 head gaskets
[Re: Get-X]
#1049862
08/20/11 02:00 PM
08/20/11 02:00 PM
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Joined: Aug 2004
Posts: 1,047
Arizona
68CoronetRT
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Quote:
It will vary a lot depending on the valve job and the valve head. Put a set of valves in that have a flat head replacing the OE dished head valves and you'll see different cc values.
These already have the 2.14/1.81 valves with hardened seats installed so the surface is flat.
I'll need to use the plexiglass method to be sure of my results either way.
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Re: 440 head gaskets
[Re: 68CoronetRT]
#1049863
08/20/11 05:57 PM
08/20/11 05:57 PM
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Joined: Oct 2003
Posts: 3,698
NE Oklahoma
Von
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master
Joined: Oct 2003
Posts: 3,698
NE Oklahoma
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A set of 452s I have measured 4ccs less with just a valve change.
72 RR, Pump gas 440, 452s, 3800 lbs, Corked, ET Radials,. 11.33@117.72.
Same car, bone stock 346s, 9.5 comp, baby solid. 12.24@110.
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Re: 440 head gaskets
[Re: 68CoronetRT]
#1049867
08/23/11 09:43 AM
08/23/11 09:43 AM
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Joined: Jan 2003
Posts: 74,978
U.S.S.A.
JohnRR
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Quote:
A 12cc hypodermic needle. Slow but with the plexiglass it was easy to see when full.
I know its not the ideal way but its all I have hence the reason I did it 3 times in each chamber.
Did you use a yardstick to measure the head bolt boss also ?  , laugh , it was a joke
Something is not right to me , your 2 numbers do not jive.
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Re: 440 head gaskets
[Re: JohnRR]
#1049868
08/23/11 11:39 AM
08/23/11 11:39 AM
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Joined: Aug 2004
Posts: 1,047
Arizona
68CoronetRT
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I know it sounds silly but hey you use what you have on hand. As for the bosses I used micrometers so I am certain on those measurements. Also, I sent a request to the original owner of the heads who had the valves replaced to find out if they cc'd them at that time. I post the numbers if he sends them.
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