Go Back   The Ford Barn > General Discussion > Model A (1928-31)

Sponsored Links (Register now to hide all advertisements)

Reply
 
Thread Tools Display Modes
Old 07-24-2014, 11:45 PM   #1
Egov
Junior Member
 
Join Date: Jul 2014
Location: Aurora, co
Posts: 7
Default head specs

Hey everyone! Just got my 1930 aa running and noticed a little head gasket leak. Figured I'd pull it and have it milled a little for higher compression. My machinest told me to get all the specs and measurements for the head(he's done big flatheads but never a model a) just to make sure its stock and hasn't been cut before. Does any one know where I can find these specs?
Bert's model a is about 25 minutes from my place but ya know the more information the better!!

Also has any one done the t5 tranny swap into a aa yet and if so what kit did you use and was it pretty basic to do or a pain?

Sorry bout repeating the t5 stuff, new to the model a world at 24 years old lol
Egov is offline   Reply With Quote
Old 07-25-2014, 12:16 AM   #2
Mike V. Florida
Senior Member
 
Mike V. Florida's Avatar
 
Join Date: May 2010
Location: South Florida
Posts: 14,054
Send a message via AIM to Mike V. Florida
Default Re: head specs

Little higher compression is right. You are FAR better off with a commercial HC head as there is more to it then shaving the head, the combustion chamber is a different shape in true HC heads.
__________________
What's right about America is that although we have a mess of problems, we have great capacity - intellect and resources - to do some thing about them. - Henry Ford II
Mike V. Florida is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 07-25-2014, 02:38 AM   #3
Dodge
Senior Member
 
Join Date: Nov 2011
Location: Sonoma, CA.
Posts: 1,497
Default Re: head specs

You can't take enough off to make a difference. Go for a Snyder head your money
will be well spent.
Dodge is offline   Reply With Quote
Old 07-25-2014, 05:17 AM   #4
Tom Wesenberg
Senior Member
 
Tom Wesenberg's Avatar
 
Join Date: May 2010
Location: Mpls, MN
Posts: 27,582
Default Re: head specs

I agree, shaving the stock head is like a spit in the ocean. You are lucky that Bert's is so close to you. My friend and I picked up high compression heads from Bert's when we stopped there some years back. These are the Snyder's 5.5 heads.
Tom Wesenberg is offline   Reply With Quote
Old 07-25-2014, 11:29 AM   #5
Charlie Stephens
Senior Member
 
Join Date: May 2010
Location: Southern California
Posts: 7,033
Default Re: head specs

Although the head is a couple of inches thick the thickness between the head surface and the water passage is not very much and milling enough to increase the compression will probably result in cracks. When I find a head that has been milled very much I pass on it. You can tell how much a head has been milled by looking at the depth of the recess to clear the piston. Another problem you might encounter is the piston hitting the milled head, be sure to check to see if your piston comes above the surface of the block (from the block being surfaced over the years) and that there is enough clearance. My suggestion is as others have said, buy a high compression reproduction cast iron head and don't even mess with the stock head. Note that the head in the photo is an A 6050B head (Police head) but the area of concern is the same.

Charlie Stephens
Attached Images
File Type: jpg IMG_7905.jpg (72.0 KB, 45 views)
File Type: jpg IMG_7906.jpg (62.3 KB, 43 views)

Last edited by Charlie Stephens; 07-25-2014 at 12:47 PM.
Charlie Stephens is offline   Reply With Quote
Old 07-26-2014, 02:08 AM   #6
colin1928
Senior Member
 
colin1928's Avatar
 
Join Date: Mar 2013
Location: Australa Melbourne
Posts: 878
Default Re: head specs

Sponsored Links (Register now to hide all advertisements)
On a stock A Model engine you need 0.030 + all your clearances
i e con rod bearing gap + main bearing gap + piston rock
aim for 0.040 cold piston to head clearance
head gasket manufacturer will supply compressed thickness
colin1928 is offline   Reply With Quote
Old 07-26-2014, 05:32 AM   #7
James Rogers
Senior Member
 
James Rogers's Avatar
 
Join Date: May 2010
Location: Asheville,NC
Posts: 3,104
Default Re: head specs

I have used heads like the one Charlie shows and have never had a problem with clearance. I have an 8:1 head that is flat with no counterbore used with a copper gasket and it does not hit.
As far as cutting the stock head to increase compression, I have one that has been cut .125 and it didn't increase the ratio but about .02.
James Rogers is offline   Reply With Quote
Old 07-26-2014, 09:56 AM   #8
ctlikon0712
Senior Member
 
ctlikon0712's Avatar
 
Join Date: Feb 2011
Location: Cocoa, Florida
Posts: 1,609
Default Re: head specs

I would just re-torque the head first to 55 Ft lbs. and see if it fixes the leak. The combustion chamber is shaped so differently from a stock head to the high compression type that shaving doesn't get you much for what you pay to have it done.
For the T5 question, use the search feature and go advanced. Then enter your criteria and check the Model A section and you will most likely find all the answers to your A related questions.
__________________
Wanted: Simmons Super Power Head
Craig Likon 1931 150B
ctlikon0712 is offline   Reply With Quote
Old 07-28-2014, 09:02 PM   #9
Egov
Junior Member
 
Join Date: Jul 2014
Location: Aurora, co
Posts: 7
Default Re: head specs

Thanks for your input everyone! Gonna have to break open the piggy bank for a new head but think it'll be worth it in the long run!
Egov is offline   Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 09:49 AM.