Identify head/engine

R

Rickrey

Junior Member
Good Morning,
Can anyone identify this cylinder head— marked F.
Also, is this likely a 1940 engine or later 40s ?

Thanks

I don’t seem to be able to attach a picture.
 
Heads for 40 marked "F" are aftermarket. 40 car 85 HP used the cast iron "A" head which also has Ford part number on the upper edge. This head was used by Ford since 38 and there are modifications to the head over these years.
 
Yikes ! I’m sorry. The heads are marked with an A. I don’t know where the F came from.
This is an engine in a 40 Ford. So, likely it is a stock 85 horsepower engine ? Correct?

Thanks
 
Rickrey said:
What’s the difference between the A head and the 59 A-B head ?
Click to expand...

The A heads are respective of side they are to be installed upon.
The 59AB heads can be installed on either side.

The heads, A vs. 59AB have different combustion chambers. Installing A heads on a later engine ('42 - '48) will not have a happy ending as the valves will slam into the head.
You can install 59AB heads on a '40 block but you will lose a bit of compression. I am not certain if they would otherwise affect performance.

Likely, it is a '40 engine. It may be a '38 - '41 as well. The A heads fit on all of those engines without issue.
 
My right side head has a crack at the front edge — weeps coolant. So, it would be simplest for me to try to find a pair of A heads for replacement ?
What would be a safe amount to shave for a bit more compression ?
Thanks
 
Rickrey said:
My right side head has a crack at the front edge — weeps coolant. So, it would be simplest for me to try to find a pair of A heads for replacement ?
What would be a safe amount to shave for a bit more compression ?
Thanks
Click to expand...

A heads are fairly easy to find. I suggest you speak with Mike Driskell.

There is no definitive answer as to how much you can mill the heads.
Were they milled previously?
There are a few guys here on the Barn that can offer good advice as to how you must go about figuring out how much can be milled.

With an otherwise stock engine, milling for a bit more compression will not make a discernable difference in performance.
 
When milling heads, the concern is piston clearance with the head. Folks generally use something like aluminum foil or modeling clay rolled up in little balls to place in the chamber and then torque the head with an old head gasket to check. A person doesn't want much less that .050" overall clearance. Make sure both sides are milled approximately the same amount during set up to maintain compression integrity.
 
I second what "rotorwrench" wrote. Over the last 3 engines I have done, I have found that custom fitting the heads to have the proper clearance over the piston produces the proper "quench" in the combustion chamber and brings compression up to a good level. This produces the most efficient combustion which helps both power and economy.
 
If you're going to mill the heads, one needs to measure the piston crown height at TDC on BOTH cylinder banks. Frequently one side will have a different height than the other. I always shoot for .040 to .045 of quench . . . really helps improve the performance of a flathead.

Also, depending on whether or not you have a high-performance/high-lift cam, you'll want to measure the valve clearance at the top of the valves (where the eyebrow section of the chamber resides). I like to have about .060 over the valves (or more) - this is on the TOP edge as the valves are canted and the top is where they are most likely to have interference with any particular head.
 
You must log in or register to reply here.
Back
Top