Thick head gasket needed

C

captain j

Member
I recently got a winfield head 6.8:1. There is no relief cut for the piston and my piston comes up about .055 above the block. The gasket i have is only .60 and thats not compressed yet so much know this isnt going to work. I used a copper felpro 7013 previously and after i took that off its reading approx .080 thick. Is .020 enough clearance to work or does someone make a thicker head gasket to solve my clearance issue. Im not pulling the pistons to have them cut down. Someone mentioned a felpro 7013c???? Is that tjicker than the 7013 or basically the same thing?
 
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Copper gaskets unlimited (coppergaskets.us) makes a .125 thick solid copper gasket. .020 squish is super tight, even for racing applications. I like .040 for small engines and .060 for larger, so the .070 of the .125 thick gasket is about right.

They have model A and B patterns.

I haven't used one on an A but it ought to be fine. Solvent wipe it and spray with copper coat both sides.

Spendy though.
 
This is backwards.
The piston is never supposed to protrude above the head. The region between the piston and the head is called the 'quench' area. The engine will not run right if there is a piston in it. Look it up.
There are some here who maintain Ford ran the pistons .032 above the deck. Talk to the old timers who pulled original motors apart years and years ago and they will tell you this is just not true.
The correct solution is to have the pistons cut and re-balanced. Not a big deal.

Besides, why have a 6.8:1 head if you are gonna shove more gaskets in there which will lower the compression.
 
If i had the pistons cut so they were flush with the top of the block and ran a copper gasket which is .080. Then ran that with the winfield head thats .080 clearance between top of piston and head.
If i left piston alone (.055 above block) and just ordered a .125 copper gasket that would leave me .070 clearance from top of piston to head.
Seems like a lot less work and money to just get a thicker gasket and i would end up with a better compression. I emailed the coppergaskets.us to see what they say.
 
Best Squish is obtained with .035 to .050 clearance between piston & head.
More than .050, no squish is obtained. Bad
May want to inquire at Best Gaskets or Cometic for a gasket made to your thickness needs
 
tbirdtbird said:
This is backwards.
The piston is never supposed to protrude above the head. The region between the piston and the head is called the 'quench' area. The engine will not run right if there is a piston in it. Look it up.
There are some here who maintain Ford ran the pistons .032 above the deck. Talk to the old timers who pulled original motors apart years and years ago and they will tell you this is just not true.
The correct solution is to have the pistons cut and re-balanced. Not a big deal.

Besides, why have a 6.8:1 head if you are gonna shove more gaskets in there which will lower the compression.
Click to expand...

Anybody thats done a few Model A engines knows that the stock pistons protrude about .032 above the deck!
My 30 coupe, original engine, stock bore protrudes .032 above the block.
Bill
 
the continuing propagation of incredibly wrong info on this site is a major reason I have stopped, and now will stop again.
People are merely looking to have an incorrect method that they have come up with verified by someone, anyone, so that they may proceed with their plan and save 5 bucks. No one is actually looking for the correct way to do things. You know who you are. And again talk with the old old timers and you will see you are dead wrong about the .032 figure. Something else occurred to have that happen; that was not how they were originally
 
I had a similar problem with my engine. I took the head (an aluminum crows foot Winfield) to my local Hi-Performance machine shop to have it fly cut. The machinist recommended I use a standard head gasket, then a solid copper head gasket and then another standard gasket. It's been working great for over 3 years now. I got the copper gasket from Clark Copper Head Gasket Co. They use this system on some of the racing engines they worked on. If I later need to put the head on an engine with standard pistons, I haven't lowered the compression ratio of the head.
 
I have taken apart hundreds of Model A and B engines and EVERY one the pistons protruded some above the block. Now to the original question- I have run heads without the counterbore up to 8-1 compression and never had a piston to hit the head.
 
I also have taken my fair share of A/B Model engines apart and always seen some piston pop up I have also seen some variation in the C.H of piston manufactures over the years
You want at least 0.040" clearance for heat expansion and stretch/flex
I have used 2 gaskets with mixed results ( long time ago) I would recommend a thicker copper gasket or fly cut the head
 
Anyone used a head gasket shim on theirs? I have a winfield 7:1 and same thing...no fly cut and pistons protrude about .045. I checked the quench and had .015 clearance above the piston. I hear .040 is about the minimum you want to have. I ordered a .030 shim...we'll see if it works I guess...
Also my stock engine I just pulled out as well as my new one both have pistons above the block...before ordering the shim I did call around to several machine shops with no luck finding anyone to fly cut the head locally. I called innovative machine and the guy told me they sell 20,000 shims a year so I imagine they work ok on at least the modern engines.
 
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Here's the shim it was about 30 bucks shipped...worth a try I suppose.
 

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tbirdtbird said:
the continuing propagation of incredibly wrong info on this site is a major reason I have stopped, and now will stop again.
People are merely looking to have an incorrect method that they have come up with verified by someone, anyone, so that they may proceed with their plan and save 5 bucks. No one is actually looking for the correct way to do things. You know who you are. And again talk with the old old timers and you will see you are dead wrong about the .032 figure. Something else occurred to have that happen; that was not how they were originally
Click to expand...

This comment seems to be missing the point. Even if a protruding piston isn't stock, it is there now. The probable cause is a few resurfacings over the century. The only solutions are non-stock rods, non-stock crank, non-stock piston, non-stock head, or non-stock head gasket. I'd pick the gasket as the cheapest, and most adjustable, version. I mean, you aren't advocating welding up the whole block surface and refinishing are you?
 
The .040 clearance is what JandE recommends. In a SBC the piston rod assembly can stretch as much as .035 when stressed. Solid copper head gaskets are usually used on high compression engines that ordinary head gaskets cannot seal the compression. Solid copper gaskets are prone to seepage/leakage. Ask me how I know! Quite a few A blocks had .032 popup when new. some say all. We need Marco and his research on this. The best fix, although I understand he doesn't want to do it, would be to machine the top of the pistons. If you are going to use an aftermarket high compression head you really should do it right in the first place and quit trying Mickey Mouse the job . But you go right ahead it is your car after all.
 
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Simonpie said:
This comment seems to be missing the point. Even if a protruding piston isn't stock, it is there now. The probable cause is a few resurfacings over the century. The only solutions are non-stock rods, non-stock crank, non-stock piston, non-stock head, or non-stock head gasket. I'd pick the gasket as the cheapest, and most adjustable, version. I mean, you aren't advocating welding up the whole block surface and refinishing are you?
Click to expand...

'this comment seems to be missing the point', you're wrong ! I didn't 'seem' to miss the point...IT didn't only miss the 'point', it really does mislead and misinform.
Some of the best guys (machinists/builders/engineers, racers, etc) on this board/forum, have informed of the FACT that Ford had +/- .032 piston above deck when he built the engines. Although I am a neophyte at this, this is my experience also.

Hey captain,
Now to the problem/question. There are a number of things that can be done to mitigate/deal with the situation as stated. I myself have dealt with this piston 'popup' by cutting down the piston tops on two B engines. First time done was on the B engine that runs (great) in my A. This was done with the engine in the car and by hand tools :eek: ! This engine runs great.
My present B project pistons were cut down by the engine shop, because the shop owner screwed up the piston specs and order. I used Egge pistons and am expecting a great running engine :rolleyes: !!
Also, flycut process can be utilized to correct situation. Also , head gasket thickness adjustment can correct situation (maybe least expensive). And, a different style head can be used, although this may go against your 'grain' of having bought/use the desired /best head for you piece of mind,eh :).
Pay no attention to denigrating remarks, as to your having no knowledge, etc, as that is not only wrong info...but also rude and against Ryan's ethical/behavioral rules for this great forum. Good luck and please let us know what works for you ;)
 
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For all of us that don't know the answer, but for some of us that are at
least willing to ask the question;how about posting the information for
"Innovative Machine" regarding their phone # and also address....
I, for one, could also use this solution to solve an existing problem that I
had nothing to do with creating it! Sometimes a band aid and super glue are a far better solution than bleeding to death while on the way to the emergency room :eek: ............. :rolleyes:
 
steve hackel said:
For all of us that don't know the answer, but for some of us that are at
least willing to ask the question;how about posting the information for
"Innovative Machine" regarding their phone # and also address....
I, for one, could also use this solution to solve an existing problem that I
had nothing to do with creating it! Sometimes a band aid and super glue are a far better solution than bleeding to death while on the way to the emergency room :eek: ............. :rolleyes:
Click to expand...

Hey Steve,
Good to hear that you are still active :) !

If it is solid copper head gasket that you are speaking of, the Clark Copper Gasket Company does make custom head gasket thicknesses. Just Google the name , for other info. I have info somewhere, but it keeps hiding from me :o
 
Innovative machine and supply. Www.innomach.com
636-825-3335. They also make the thick solid copper gaskets. I opted for the shim because a) price b) I already had a new head gasket and c) I really want to see how it works.
 
While i have no real word experience with solid copper gaskets I got the impression that they were not meant for street use. I was going to install a solid copper gasket on my Chevrolet head powered Model T and the info that I read at several of the sites was that they were for strip or racing where the head was removed often and the gasket could be re annealed also something about sealing between the block and head at the water passages.
Wouldn't it be better after find your clearances just have the head flycut and use a single gasket?
 
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