Head bolts too short for High Compression Head

GOW said:
so then,what is the fix?
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Anyone told, or gotten a response from, Snyder's?
Sounds like their head is to thick and they should offer a solution.

Additional thought.....
If indeed the head is approx. 1/4" thicker than stock.....what effect, if any, is there on the distributor shaft which now becomes 1/4" to short?
 
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GOW said:
so then,what is the fix?
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The fix or solution is obvious. Either do nothing and live with it ... OR change the dimensions of the head ... OR look for longer than original studs (in Grade 8).


Tom from Drippin' said:
Additional thought.....
If indeed the head is approx. 1/4" thicker than stock.....what effect, if any, is there on the distributor shaft which now becomes 1/4" to short?
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Fortunately there's some room to sneeze with the distributor shaft but it's possible the tang might be barely engaged which is not good. If it ever gives trouble the dimension of the head will have to be changed (if it's indeed not correct as is) or a longer shaft will be necessary.




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...or get some 4" 7/16-20 grade 8 bolts, cut off the heads, and die cut the 14TPI threads on the other end. It helps to have a lathe to face and chamfer the cut end, and to hold the die square during the cut - they tend to wander if hand-held.
 
brucesp said:
...or get some 4" 7/16-20 grade 8 bolts, cut off the heads, and die cut the 14TPI threads on the other end. It helps to have a lathe to face and chamfer the cut end, and to hold the die square during the cut - they tend to wander if hand-held.
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A grade 8 bolt is fairly hard material and will cut a sorry thread at best when cut with a die as you suggest.

A person could also just forget the studs and use bolts but they would have to be grossly over-torqued to get enough clamp with the coarse block threads (which is not good for the block or its threads).




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Hmmm. Not sure I agree with your first point. I cut threads on grade 8 bolts all the time. A new, good (USA), sharp HSS die and RapidTap produces decent results. But that is why I suggested die cutting the coarse threads instead of the fine threads. The studs are designed to be hand-threaded on the coarse end, and torqued on the fine end, which draws the head down and tensions the studs without putting wear on the cast iron threads in the block. Die-cut threads in that application would be fine.

Which brings me to your second point. I hope no one considers bolts, because you're right - it wouldn't be good for either the block or head. Trying to get that much tension on bolts with coarse steel threads into cast iron would be a recipe for disaster.
 
brucesp said:
Hmmm. Not sure I agree with your first point. I cut threads on grade 8 bolts all the time. A new, good (USA), sharp HSS die and RapidTap produces decent results. But that is why I suggested die cutting the coarse threads instead of the fine threads. The studs are designed to be hand-threaded on the coarse end, and torqued on the fine end, which draws the head down and tensions the studs without putting wear on the cast iron threads in the block. Die-cut threads in that application would be fine.
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I disagree, respectfully. The cast iron threads in the block are still subject to a straight pull. The high comp head requires more torque and if the threads in the block are not in near perfect shape (which describes a multitude), the sorry die cut threads in grade 8 may not adequately hold or possibly the block threads could break. Moreover, it would be hard to find a die which would match and cut the same class fit and tolerances as what Ford used.


brucesp said:
Which brings me to your second point. I hope no one considers bolts, because you're right - it wouldn't be good for either the block or head. Trying to get that much tension on bolts with coarse steel threads into cast iron would be a recipe for disaster.
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Believe it or not, I know of a well known engine rebuilder who INSISTS on bolts and routinely torques them to 80 pounds on stock heads! ...the approx. torque necessary to get an equivalent 55 pounds or so with the coarse threads.

He's been in business for more than 35 years and the last time that I talked to him he would not warrant his work unless the bolts are used. If the block threads fail or pull out he just fixes them. Evidently, a distorted block does not seem to matter to him.








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so unless you cut the head .250 you'll still have distr. problems and if you do cut the head i would guess the compression ratio would be way to high. in the end this is NOT the head to buy.........i would think someone from snyder's would offer an opinion ....
 
I talkd to Tom at Snyders this morning about the problem of hte short studs. His answere was to unscrew the stud out of the block until you has the corect length above the block and/or head. But would that not leave less threads into the block giving less holding power into the block. Thus problem not solved.

I screwed my studs into the block until they touched the bottom of the hole - not tight - just touched. Ken
 
I have an HC head 1/4" thicker than stock (not Synders) and could not find any grade 8 studs to fit at any local supplier or even on line. Went to a specialty supplier and bought grade 8 bolts with the course threads, and took them to a machinist who cut them to the length I gave him and cut in fine threads. Trouble is it was kind of expensive at shop time hourly, figured at 20 minutes per bolt to cut and thread. FSI Ignitions will sell custom length stainless distributor shafts for $27.00.
 
To GOW
I think you could mill the bosses on the head rather than the gasket surface thus not affecting the compression, however, how high are the bosses on the head. You certainly wouldn't want the nuts in a recess.

Another person to call for an opinion would be Bill Stipe. I understand he designed the combustion chamber for the Snyder 6:1 head and he also did dyno tests to compare with the 5.5 head.

Richard
Anaheim CA
 
I am in the same boat as the rest of you guys. I just put my head on last week and found the studs a little short as well. I just unscrewed out of the block until I had a full nut on top, retorqued to 55 lbs. and everything seems OK. I won't be starting this motor until after Christmas, so I am waiting to see if there is a suitable fix to this. I did have trouble putting the spark plugs in and phoned Tom. He offered to send me a tap to fix it, but being in my usual rush to put a check mark on my list, I declined and just bought one locally. The water outlet studs on mine are about 1/4 to 3/8" above the nut. Hmmm, maybe I will change them.... I like the looks of a job done properly.....The thing that really concerns me now is the distributer shaft!! (thanks Tom from Drippin' and the rest of you guys) As you can tell, I have not got far yet. Any fix now takes you away from stock, and you will need to carry your own spare instead of relying on another tour member to save you! Perhaps Snyders will buy a lot of extended shafts from FSI Igitions and send us all two each for Christmas!!! If he won't, I'll have to have a couple made locally..... Is there any more good news out there on this subject?
 
kenparker said:
I talkd to Tom at Snyders this morning about the problem of the short studs. His answer was to unscrew the stud out of the block until you have the correct length above the block and/or head. But would that not leave less threads into the block giving less holding power into the block. Thus problem not solved. Ken
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Well their method fixes one end and compromises the other.

The amount of thread length that screws into the block was designed for the stock head. A significant reduction in that amount forces the remaining threads to carry all the load. Next, add the torque increase for the high comp head along with old blocks with used threads and you have a condition where some blocks may take it and some may not.

Moreover, the ones who don't like the idea of unscrewing the studs (or don't know) will have problems just as they have said in this thread.








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Sounds like that new Snyder 6.0 is presently just a "0".:eek: Either it was machined to the design print which had non-standard specs, or it was designed to Henry's spec but instead machined to ??? Either way, looks like the round-one batch is a loser. To complicate matters, if it ever gets 'fixed' (batch two?) how will anyone know the good from the bad and the ugly? Where was the head cast, and where was it machined? Here, or 'there'? An ISO shop, or a so-so shop? If anybody knows, please fill me in. Inquiring minds want to know.
 
I have installed 4 Snyder heads this year , 3- 5.5 and 1-6.1 ALL have this problem I ask Snyder if there were any plans to offer longer studs and he said NO ,just don't run them into the block all the way. I used a guage to set the depth and so far all are working good. I don't know how anyone could get the proper tourque with less than a full thread on the nuts, when I tryed the nuts stripped at 45 pounds. To get the studs to back out with the head in place I backed the nut out ( new nut ) so 1/2 the threads were exposed in the nut and put a bolt into the other half of nut and by jaming I was able to loosten stud by turning on nut. Bubby Sharp in KY
 
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Seems to me the fix is to wait and hope there's a new brumfield head comming or try to find a used one. I just can't understand selling a head that's not the correct thickness.....one would think a top of the line co. Would reacll and retool.
 
Bob Johnson said:
Paul or Model A Apprentice,

How thick is the head at the stud holes?

Bob
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Measured three holes on the right side of the 6:1: 2.309, 2.312, 2.311, or approximately 2 5/16.

Same holes on the old speed head (5.5:1 ?) measure: 2.21, 2.2, 2.21 or approximately 2:3/16.

There is a visable difference between the two heads. The head stud hole on the old speed head is milled flush to the top of the head. The 6:1 head stud hole has a "collar" which protrudes well above the head.
 
gweilbaker said:
Could the studs be threaded too far into the block? The studs cavities blown into the water jacket letting the studs enter the jacket.

Just SWAGing

GW
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The 3.5" stud has a shoulder on the course end which would preclude you from driving it too far into the block.

The 3.75 ignition stud does not have the shoulder and care must be taken not to drive the stud too far!
 
"To complicate matters, if it ever gets 'fixed' (batch two?) how will anyone know the good from the bad and the ugly? "

This 6:1 has a "collar " which extends the stud holes above the head while my speed head has the holes milled flush with the head.
 
Les Andrews mechanics handbook and other sources
has installed length dimensions for the studs. Screw them until they protrude the correct length. That should fix the problem.
 
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