The Ford Barn

CA Victoria · 01-24-2020, 10:47 AM

With a Model a head I can measure based on Henrys original specs to determine how much has been removed from the heads surface.

Has anyone collected these specs for Flathead V8 heads?
What is the allowable minimum thickness to mill a head to?
What is the allowable difference when milling or matching two used heads?

Why ask? Cuz I have this behemoth that needs to be put to work.

51 MERC-CT · 01-24-2020, 11:30 AM

Seems to me the limiting factor is the resulting clearance/squish area between piston and head (consensus seems to be .050" minimum.)

marko39 · 01-24-2020, 11:31 AM

Quote:

Originally Posted by CA Victoria

With a Model a head I can measure based on Henrys original specs to determine how much has been removed from the heads surface.

Has anyone collected these specs for Flathead V8 heads?
What is the allowable minimum thickness to mill a head to?
What is the allowable difference when milling or matching two used heads?

Why ask? Cuz I have this behemoth that needs to be put to work.

Heads should not be milled until piston clearance is measured.Depending on the block and if is has been decked the amount milled on heads can vary between heads.

philipswanson · 01-24-2020, 12:44 PM

I have always had more trouble with valves kissing the head first, not pistons. you need to measure valve clearance as well. A cam will not cause pistons to hit, only valves.

Ol' Ron · 01-24-2020, 04:11 PM

You might want to use heads of the same type and match them. Howeve you might have to redome onr. I;t;s easy to make a doming tool out of an old file like I did, However it has to ture very slow to prevent chatter due to the small dis in the center and large at to edge, to keep chatter down. Not much of a problem in aluminum.

CA Victoria · 01-24-2020, 06:07 PM

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Good info Ron, using a file is a good idea too.
.....my list is longer than there are hours in the day. Projects on the Bridgeport are fun.

If I don’t find the data I will start another page in my notebook to capture measurements off of NOS heads.

Ol' Ron · 01-24-2020, 11:50 PM

I have some pics of the doming tool which Ill post. I also made a fis
xture from pipe fittings for grinding the radius, But I can't find them. ET!!

Ol' Ron · 01-25-2020, 07:28 AM

Now that you can mill the heads, you might want to try angle milling them. Taking material off over the valves. A stovk car trick was to take .060" off the valve side iff the heads.

01-24-2020, 11:30 AM	#2
51 MERC-CT Senior Member Join Date: May 2010 Location: East Hartford, Ct Posts: 5,898	Re: Heads Seems to me the limiting factor is the resulting clearance/squish area between piston and head (consensus seems to be .050" minimum.) __________________ DON'T RECALL DOING SOMETHING FOR MYSELF BASED ON SOMEONE ELSE'S LIKES OR DISLIKES

01-24-2020, 12:44 PM	#4
philipswanson Senior Member Join Date: Oct 2015 Location: Bonita, CA Posts: 1,374	Re: Heads I have always had more trouble with valves kissing the head first, not pistons. you need to measure valve clearance as well. A cam will not cause pistons to hit, only valves.

01-24-2020, 04:11 PM	#5
Ol' Ron Senior Member Join Date: May 2010 Location: Chester Vt Posts: 8,855	Re: Heads You might want to use heads of the same type and match them. Howeve you might have to redome onr. I;t;s easy to make a doming tool out of an old file like I did, However it has to ture very slow to prevent chatter due to the small dis in the center and large at to edge, to keep chatter down. Not much of a problem in aluminum.

01-24-2020, 06:07 PM	#6
CA Victoria Senior Member Join Date: Feb 2011 Posts: 2,111	Re: Heads Sponsored Links (Register now to hide all advertisements) Good info Ron, using a file is a good idea too. .....my list is longer than there are hours in the day. Projects on the Bridgeport are fun. If I don’t find the data I will start another page in my notebook to capture measurements off of NOS heads. __________________ Tim Downtown, Ca

01-24-2020, 11:50 PM	#7
Ol' Ron Senior Member Join Date: May 2010 Location: Chester Vt Posts: 8,855	Re: Heads I have some pics of the doming tool which Ill post. I also made a fis xture from pipe fittings for grinding the radius, But I can't find them. ET!!

01-25-2020, 07:28 AM	#8
Ol' Ron Senior Member Join Date: May 2010 Location: Chester Vt Posts: 8,855	Re: Heads Now that you can mill the heads, you might want to try angle milling them. Taking material off over the valves. A stovk car trick was to take .060" off the valve side iff the heads.