Milling a Snyder's head

Jim; What is your impression (review) of Schwalms?
Hiker,Ora builds a good motor.He did the babbiting,set the crank and installed the pistons and rods.I did everything else.I have about 7000 miles on the motor and does not use a drop of oil or leak any oil.I'm very satisfied with the finished product.He may be a little pricey,but does top notch work.It drags my 30 Tudor around with no problem and will do 55mph all day long.:D
 
Most likely, the casting had not stabilized before it was finish milled for sale. Did you ever buy a set of rotors, only to find they "warped" a few months later? Same thing.

new quality made rotors are true out of the box ,if they are not i consider them defective. if they warp 3 mths down the road there is a reason for that. usually caused from hard braking, tight caliper slides, restricted brake hose, tight caliper pistons, improper hard linings among other reasons..
 
The heads were probably "green" when machined. (the castings were not seasoned)
you should let them sit for a while before machining, not always possible or practical)
I know when we sold a lot of brake drums the manufacturer sent them undersize using
the normal distribution process to let them season and we had to turn everyone of them
as we sold them.

Dodge
 
I have installed 5 high compression 5.5 heads, all 5 needed to be broached milled before I could install them, They were twisted.

Mike
 
I had same problem with Snyders cast iron exhaust header, it was warped new out of box.You could put an .018 feeler gauge between block and header on both outside ports.
 
Would broaching/milling .060" off a Snyder's cast iron 6:1 HC head make it a 6:7-6:8 head?

Is the flatness problem the same for cast iron & aluminum heads?
 
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Would broaching/milling .060" off a Sander's cast iron 6:1 HC head make it a 6:7-6:8 head?

Is the flatness problem the same for cast iron & aluminum heads?

I assume you mean Snyders? Not a cc expert so I will let some one else answer that.
 
I have a Snyder's 5.5. head on my Model A and I'm having problems with water in the oil. I took it apart the last time and I had to loc-tite the studs again and I torqued it down and retorqued it down and this week we had a parade and I noticed a little leak and it was milky. So now I'm thinking of having my son mill the head a so I know it's straight. How far can I go?

Which head gasket did you use?? Did you use any sealant with the head gasket??
 
It's "seasoning", Cast iron is funny stuff. It moves after machining when it's not properly seasoned. I think I read that SBC blocks get seasoned for two years before machining. They're left out in the weather to get all the bends and warps out of the metal. If you cast a blank and machine it soon after, almost guaranteed it will move, warp, expand, contract, somewhere on the part. The previous example given of rotors shows the problem perfectly.
Terry




new quality made rotors are true out of the box ,if they are not i consider them defective. if they warp 3 mths down the road there is a reason for that. usually caused from hard braking, tight caliper slides, restricted brake hose, tight caliper pistons, improper hard linings among other reasons..
 
I remember Larry Brumfield talking about a problem with a few warped heads on the old Ford Barn.

As I remember it, Larry also traced it down to one new machinist who was not clamping the heads correctly.
 
All these comments and complaints are about Snyder's heads Are the other vendors any better or are they all made by Snyder's (or whoever makes Snyder's)?
 
Where do these theories come from?

Seasoning blocks for two years before machining?

I read a long while back that the big thing with drag racers was to find "seasoned" BBC Blocks that spent their life in a taxi. Don't know if it is true but makes a good story...:p:p
 
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It's "seasoning", Cast iron is funny stuff. It moves after machining when it's not properly seasoned. I think I read that SBC blocks get seasoned for two years before machining. They're left out in the weather to get all the bends and warps out of the metal. If you cast a blank and machine it soon after, almost guaranteed it will move, warp, expand, contract, somewhere on the part. The previous example given of rotors shows the problem perfectly.
Terry

Oh kinda like firewood
 
I have used a few Snyder,s heads and never found one that was not flat. Are you sure you are checking them right. You might be worse off with some machinist that is not clamping then correctly. It is not that easy to machine a head with out the right fixture.
 
I have used a few Snyder,s heads and never found one that was not flat. Are you sure you are checking them right. You might be worse off with some machinist that is not clamping then correctly. It is not that easy to machine a head with out the right fixture.

See post #14. I think they maybe qualified
 
For more info on the subject of "seasoning" and "Dimensional stability" google The Practical Machinist. I googled "seasoning cast iron engine blocks" there are many articles and opinions, both pro and con.
Terry
 
I honed my stock head for an hour or so. using a aluminium level as a straight edge. also did intake and exhaust. the exhaust was bad and took a few hours and some heavy filing. I had some raising on my block around the stud hole in the back. slid the file over the bump a few times and oil honed the block all 4 intake stud holes were bulged. My dad showed me the method. he was a machine repairman for GM's saginaw steering gear. Its a lot of honing and checking. Another thing about honing. It will show you those high spots right away. but to clean those lows will cost you some time.
 
Just curious, How 'flat' should a head be. I realize as flat a possible but is, say, .005" acceptable? Thanks
 
A friend has a Snyder 5.5 head that is about 1/8" shorter on both length and width. Are they all like this or is his unique? It looks kind of strange.
 
I wouldn't put my self through all that. First off, how do you know it didn't just reproduce the the highs and lows of the old surface. Actually, if you had a large piece of thick plate glass, you could have used it for a lapping plate. But, But, the lapped finish is too fine to hold a gasket. It's almost a polish. I never worked in an automotive machine shop. ( I worked in Job shops and Die shops and finally a Model Shop) So i'm not familiar with the specialized machines that are used in that trade.The only make of machine that comes close is the Blanchard grinder ( Large segmented stone against a rotary magnetic table) A large Blanchard grinder is an awesome machine! But most guys refer to something called a Van Norman broach. Van Norman built milling machines for the war (WW2) in the forties. I didn't even know they were still in business. I haven't a clue how they were configured.
Terry




I honed my stock head for an hour or so. using a aluminium level as a straight edge. also did intake and exhaust. the exhaust was bad and took a few hours and some heavy filing. I had some raising on my block around the stud hole in the back. slid the file over the bump a few times and oil honed the block all 4 intake stud holes were bulged. My dad showed me the method. he was a machine repairman for GM's saginaw steering gear. Its a lot of honing and checking. Another thing about honing. It will show you those high spots right away. but to clean those lows will cost you some time.
 
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