SBC Head Gasket choice.

dfarr67

Active Member
In a previous life the block was 0 decked then stroked to 383 and now the pistons sit out of the hole .015in, bore is 4.040in. Looking at readily available stock. Block wasn't particularly finished for MLS, heads Alum afr. Cometic isn't a choice. Daily driver. GMPP is the tightest at 4.100in. The GMPP and Mr G have smaller cooling holes mid way up the gasket on the intake side.

FL 1044
FP 1144-53
Mr G 5799G not much info on these
GMPP 12557236
 
http://www.jegs.com/i/SCE-Gaskets/829/T ... tId=753475

1 800-GASKET-0 (427-5380)
829-T11066.jpg

copper head gaskets come in several designs, the embossed version above is fairly common and used like most other head gaskets

the solid copper head gasket is generally used with wire o-rings in the block, but Ive used them for decades with zero problems without the wire o-rings


copperh2.jpg

copperh1.jpg

copperh3.jpg

copperh4.jpg


headgasjk.png


copperspray1.jpg

bolthread.png

yeah! the gaskets linked above ARE expensive and yeah I'd call SCE before ordering them, but they seem to be a perfect choice, and they are darn good gaskets
1-661-728-9200
Ive used COPPER HEAD GASKETS FOR DECADES WITH ZERO FAILURES


https://www.napaonline.com/en/p/BK_7001006
I usually use this sealant (sparingly)on the course ends of main cap studs that screw in hand tight, and ESPECIALLY on head studs that enter water jackets
read these threads


http://www.permatex.com/products/Automo ... ealant.htm




headboltswithwash.jpg

alumimum heads ALWAYS require head bolt washers and the flat surface faces the head the inner bevel faces the bolt head
on head STUDS the same things required on aluminum heads to get even clamp loads and no galling




80057.jpg

this stuff is pretty much interchangeable
80063.jpg


with this stuff in THAT APPLICATION
recommended operational temp range is just a tiny bit different from what Ive seen, one has about a 30F higher recommended temp, youll never get close in a properly operating engine to either
DisplayImagesd.asp.jpg

I can,t remember using this stuff but it appears to be similar

you need to use a thread sealant on the thread that remains semi flexiable, so you don,t apply any sealant to the studs threads while honeing the block, and only install that thread sealant on the threads within an hour or so of torqureing the stud threads with the heads in place during the final assembly so the sealant firms up in its operational location under the loads and pressure conditions its suppose to deal with, if you use a non-flexable thread sealant well in advance of final assembly your changing the thread loads and block distortion and more than likely effecting the sealant on the thread distribution, that can lead to coolant leaks

both of these work great at sealing head bolt threads, and freeze plugs etc.

be aware that head bolts enter the block coolant passages,
so if you failed to dip the bolt threads in sealant when they were assembled,
through the heads coolant can seep up along the head bolts,
into the area under the valve cover
yeah! Ive been using the solid copper gaskets in the correct thickness for each application that state they require O-rings, and NOT using o-rings
PERSONALLY HERES WHAT I FOUND WORKS BEST, BY simply spray both sides too well coat the head gasket with COPPER COAT SPRAY, let the first coat dry for 15 minutes then re-spray, then installing them damp and torquing down the heads, NO NOT what the manufacturer suggests but its worked without issue for decades. I picked up that bad habit because this type, (solid copper head gaskets cut from a sheet of copper) are CLEAN AND REUSE, and most of my mentors did it without issues well before I started racing

http://www.summitracing.com/parts/sum-111502/overview/
sum-111502_cp.jpg



http://scegaskets.com/tech-faqs/

SCE head gasket part numbers tell you the gasket type, engine family, bore opening and thickness.

  • Alpha prefix determines the type. P=Pro Copper; S=ICS Titan; T=Titan
  • First two numerals are engine family. Searching within the website or catalog by engine make will provide this information.
  • Next two numerals are 1st & 2nd decimal places of the Bore opening. The whole number (left of the decimal place) is assumed to be known.
  • Last numeral is thickness: 2=.021″; 3=.032″; 4=.043″; 5=.051″; 6=.062″; 7=.072″; 8=.080″; 9=.093″
The legend below illustrates the SCE head gasket part numbering logic.



DAMN NEAR EVERY-TIME I READ SOMEONE DISCUSS A COPPER HEAD GASKET THEY MENTION THEY NEED (o-rings) WHILE THIS IS A GOOD IDEA WITH A SUPER-CHARGER, OR USE OF NITROUS, I,VE USE SOLID COPPER HEAD GASKETS
without AN O-RING ON DOZENS OF ENGINES WITH zero failures, now theres certainly benefits to machining the engine surfaces for the o-rings provided its done correctly but I don,t see the need unless your running a turbo, nitrous or a super charger
Fig8a.jpg


Fig8a.jpg


As published in AERA Magazine by Ryan Hunter, President, SCE Gaskets, Inc.

Let's dig into it because there are applications (perhaps more than you think) for which copper head gaskets are the best choice. To be sure, copper has been around for a while and with good reason. Let's walk through some of the attributes and benefits unique to copper, then we'll get ready to put them on.

Malleable: Copper is stronger than any composite head gasket yet still malleable so it conforms to the sealing surfaces. This strength-malleability combination is, more than any other attribute, the ‘selling point’ of copper as a head gasket material over other materials. While the advantages of strength are self evident, the benefits of a malleable gasket body are somewhat more nuanced. Simply put; conformity makes a tighter seal which will show up in lower leak down percentages.

Metal-to-Metal: To an engine builder, the words “High Performance” pre-suppose high pressure, high pressure requires a more robust combustion seal and the best combustion seal is metal-to-metal. I'll elaborate; many cylinder head gaskets are coated with sealants designed to eliminate fluid leaks. From experience, readers of this article will be familiar with the various types from slick to sticky and while these work well for fluid sealing they are not able to withstand combustion pressure and heat. No matter how good an elastomeric coating may be for coolant or oil, it will eventually scrub off, burn off, or blow off the fire ring area of the head gasket and in performance engines this can happen in a surprisingly short period of time. Once the sealant is gone from the fire ring combustion seal it's a short trip to the nearest coolant passage. Silicone, or other rubber-like sealants or coatings should never be placed on the combustion seal in performance engines.

Options: Copper comes in a wide range of thickness choices; (from .021” to .093” in roughly ten thousandths increments) providing the options necessary to optimize piston to valve, piston to head and in wedge combustion chambers, piston to quench area.

Conductivity: Copper is the standard for conductors, in head gaskets we don't care about electricity but we do deal with heat. Superior conductivity benefits performance and racing engine builders in two primary ways: A. block & head temperatures are more even. B. Combustion chamber hot spots are dissipated quickly. Cylinder block/head temperature parity is an aid to tuning, though frankly, it's a minimal factor until you reach the narrow end of the tuning window. The big advantage of conductivity is in the combustion chamber area. In and around the combustion chamber standard composite head gaskets and MLS head gaskets are somewhat insulated from the cylinder head and block by the facings and coatings respectively. Heat related failures occur more often with composite and MLS head gaskets than with copper because the heat is trapped within the gasket body allowing hot spots to intensify, whereas the copper being both a better conductor and having direct contact with the block and head (remember metal-to-metal) transfers the heat to the heat exchanger, aka the cooling system, through the head and block.

Elasticity: Another interesting feature of copper, this benefit comes into play when you're out of the tuning window far enough to actually damage the head gasket. Un-alloyed or pure copper has a 25% coefficient of elasticity; cool term, here's what it means. In a 4 inch section, the copper head gasket will stretch to 5 inches before it ruptures. This gives the user a ‘safety factor’ not available with other head gasket materials. Blown, nitrous or turbocharged engines can develop cylinder pressures high enough to lift the cylinder head or push the gasket. A typical bad-actor in this regard is the small block Ford; get some good cylinder heads, add some boost or nitrous, she's goin' fast but Daddy wants more and.. the head gasket is peekin' out between the bolts. If this happens with copper the damage is apparent but the head gasket hasn't yet failed. The safety factor of elasticity allowed the copper gasket to push but still remain intact so you can either back it down & make the next round or back it down & drive home. If you push a composite gasket, game over.

Do Copper Head Gaskets Require Different Torque Values?Generally No. Fastener torque values are determined in relationship with the cylinder head and block structure. Arbitrarily increasing torque values will distort the block or head. However, there are good cases for fine tuning the torque values based upon how the head gaskets look after the first use. A nice thing about copper head gaskets is that you can ‘read’ them very easily once you know what to look for and, what to look for is evenly distributed clamp load. No gasket works in isolation, all gaskets require clamp load to do what they do and copper gaskets tell you where the clamp load is light by keeping their shine. Specifically, you want to see machining marks from the block & head surfaces transferred to the copper gasket body everywhere on the gasket. Places where the original finish of the gasket remains need some attention. Keep in mind there may be other factors in play such as, a ring dowel counterbore that has become too shallow from surfacing or a head nut bottoming on the threads of a head stud. Once you have eliminated any mechanical obstruction preventing the head from seating properly you can safely increase torque values in the light load areas by 5 to 10 ft lbs.

What about re-torquing? Solid copper (like a liquid) does not compress, it displaces. Since the copper gasket body does not compress no re-torque is technically necessary. However, since the engine build using a copper head gasket is almost always within the realm of performance or racing, I always recommend one re-torque of the head bolts after a complete heat cycle.

Block & Head Preparation for Copper Head Gaskets:Cleanliness is next to..You might be surprised at some of the samples we've received from customers asking “why did it fail?” Then again if you've been around for a while, you may not be surprised at all. I have seen head gaskets with sawdust, sand and actual small rocks embedded in them, as well as the remains of facing material from the previous head gasket. The aircraft industry has an acronym that's suitable here; FOD, Foreign Object Damage. Like leaving a wrench in the lifter valley, rocks in the combustion seal are not ok, chaos will ensue. So, as Momma taught us: let's be clean when we're doin' our duty. Use a residue-free solvent such as aerosol brake cleaner and a clean rag on the head and block sealing surfaces before assembly.

Flat: Of course the block & head should be flat within .002” across and .004” lengthwise, with surface finish of 60 to 80RA preferred, 60 to 100RA acceptable.

Combustion Sealing: Head gasket sealing is a matter of balance and more pressure is needed on the combustion seal than other areas of the gasket, this is due to the vast difference in pressures acting against the head gasket. Consider that an engine developing 1.5 to 2 horsepower per cubic inch will have between 1000 and 1200 psi in the combustion chamber while, less than 1/2” away, the cooling system is running at 22psi max. Since a standard copper gasket is flat, clamp load from the tightened head bolts will be distributed evenly unless some method is used to ‘tip the balance’ and concentrate the proper load on the combustion sealing area. When using flat copper head gaskets, the accepted method has been to install O-rings in the block or head sealing surface around the bore or chamber respectively, to accept an o-ring. What's an o-ring you ask? Simpler than you think, it's just a piece of wire tapped into a groove that sticks out enough to pinch the copper gasket. Well, maybe that's an over simplification but all you have to know from there are the proper dimensions of the O-ring groove.

Sealants Required? Yes, some method of sealing is required if the engine will be running coolant or oil through the head gasket. I state it this way because many racing specific engines either A. do not run coolant or B. re-route the coolant and oil away from the head/block mating surfaces. Since most engines run coolant and oil through the head gaskets we'll discuss head gasket sealants. Most importantly, you don't need very much; second, don’t use silicone.. that about covers it. People get into trouble with leaking head gaskets when they use too much sealant, especially too much silicone. Since the block and head surfaces are flat, the potential leak paths are very small, even with a 100RA surface finish the peaks and valleys are only about .002”, which doesn't require very much sealant to be fluid-tight. Head gasket dressings do not cure, therefore, as the head bolts are tightened the sealant ‘flows’ from the places it's not needed (peaks) but remains in place to seal the leak paths (valleys). By contrast, silicone cures to form a layer that the cylinder head can sit on, never actually coming into contact with the head gasket (refer back to our discussion about metal-to-metal above). We recommend and use both KW Copper Coat and Hylomar in the aerosol cans, simply spray a light coat on both sides of the gasket, let it ‘tack up’ for a while (no less than 2 hours) and you’re ready to bolt the heads on.

We could go into much more detail about each of these items if this was a technical manual but my hope is that this information will be of help to you when the need arises, or you need some options that are not available from conventional head gaskets.

SCE Gaskets manufactures a complete line of racing and performance gaskets including standard flat copper head gaskets of the type discussed here. As well, we offer our patented self sealing (no sealant required) copper head gaskets for use with O-rings and self sealing copper head gaskets with Integral Combustion Seal O-rings (no machining required). We also have a complete line of replacement gaskets for passenger cars, light trucks, vintage and tractor engines marketed under our Engine Master brand.

https://www.felpro.com/technical/tecblogs/surface-finish.html

PREP WORK REQUIRED
The engine’s most dynamic and critical seal, the head gasket must withstand high temperatures and casting movement to create a perfect and reliable seal. It not only must contain the extreme cylinder pressures generated during the combustion process, but also has to seal high pressure oil and the oil drain backs, and engine coolant. There are a number of variables that contribute to both the horizontal and vertical motion that occurs between the cylinder head and engine block (deck area).

Fel-Pro® uses a variety of the latest sealing technologies available to design head gaskets that conform and compensate for minor surface imperfections while being dense enough to maintain even loading between the cylinder head and block. However, even the best head gasket can’t seal a surface that is improperly prepared. Before installing a new head gasket, surface conditions of the engine block and cylinder head must be inspected and refinished if they are out of spec.


DETERMINING THE PROPER FINISH
Measuring-Surface-Finish-Profilometer-1569507750595.jpg

In order to determine an appropriate surface finish, consider the metallurgy of the head and block castings as well as the material and design of the head gasket being used in the install. Different gaskets require different surface finishes, so the surface finish must be matched to the type of gasket that is required for the application. To determine surface finish requirements, consult the OEM repair manual.

The importance of attaining the appropriate surface finish, one that matches the style of head gasket being used, cannot be overstated. Each type of Fel-Pro head gasket – whether it be PermaTorque® MLS, PermaTorque, solid or perforated core, single layer embossed steel, or other types – all require specific surface finish requirements. If the surface is too smooth, the gasket will have less "grip" and may leak; if the surface is too rough, the gasket will have a difficult time conforming to surface imperfections and may also leak. Surface finish can be checked using a surface finish comparator or a profilometer. Checking the cylinder head surface finish and flatness is an important step to take before installing a head gasket.

MEASURING ROUGHNESS WITH SURFACE FINISH COMPARATOR
Surface-Comparator-1569507750630.jpg

Roughness Average (Ra) is the average micro-inch measurement of peak-to-valley roughness height of a flat surface. The lower the Ra number, the smoother the surface. Fel-Pro recommends a finish of 60 to 80 Ra for cast iron cylinder heads and blocks and 50 to 60 Ra for aluminum.

Fel-Pro uses proprietary head gasket coatings and facing materials designed to fill in minor surface imperfections and allow for improved sealing on imperfect surfaces found in the repair environment. OEM MLS gaskets work well on new, flat, clean castings, since they require a very smooth surface finish, usually 20-30 Ra or less.

Fel-Pro’s PermaTorque MLS head gaskets are designed specifically for the repair environment and use a specialized coating that accommodates finishes as rough as 80 Ra. Surface flatness is equally important to surface finish, so always check components to ensure they are not warped or distorted. To maintain constant contact between the head gasket and mating surfaces, all deck surfaces must start out flat and remain flat after being torqued to specification. A good rule for flatness is that surface flatness, measured in thousandths of an inch, should never exceed the number of cylinders on each bank across the length of the block.

For example, no block or cylinder head should exceed .003" out-of-flat if there are 3 cylinders, as there would be in an inline-3 or V6 engine. Inline-4 and V8 applications should never exceed .004" out-of-flat and so on. No block or head should not be more than .002" out-of-flat across the width of the surface.

Learn more about Fel-Pro quality gaskets that are designed for the repair environment, find your car part, or find where to buy your auto part today.
 
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I have used the copper spray on applications. The copper gasket wasn't even on the radar- I though that application was for supercharged/turbo app's. They say 'must be used with o-rings'
 
YEAH! THAT " must be used with o-rings" worried me a good deal, for awhile also, each of us makes choices and I'm sure to advise you 99% of the time to go with the manufacturers suggestions , but after 25 or so years of using the lower head gaskets on both SBC, and BBC engines with zero failures I take that as more of a STRONG SUGGESTION, than FACT! simply because most of the guys I raced with were not using O-rings blocks and re-using the copper head gaskets and not a single guy I knew had any failures doing it!
IF YOUR SIMPLY TRYING TO GET A STOCK TPI CORVETTE ENGINE BACK IN SERVICE AS CHEAPLY AS YOU CAN?
the heads and block surfaces must be very carefully examined for damage or warping issues and if found those issues must be corrected, before any new head gaskets installed, over time steam can and will cut grooves in even cast iron blocks and rather easily in softer aluminum. no head gasket will seal a badly machined or warped head or block

btw if youve managed to blow a head gasket on a 1986-91 TPI corvette with aluminum heads
the heads and block surfaces must be very carefully examined for damage or warping issues and if found those issues must be corrected, before any new head gaskets installed, over time steam can and will cut grooves in even cast iron blocks and rather easily in softer aluminum.

keep in mind coolant must have the anti-freeze ratio set at 50%water 50% antifreeze and be replaced at least every 4 years MAX to retain its anti corrosive additives
you,ll want to place a head gasket you,ll use on the heads and mark the area inside the opening as the only areas you can change,
(notice the gasket fire ring is NOT a perfect circle like many people assume)

ideally you,ll want to un-shroud the valves while opening up the combustion chamber volume, but not extend the combustion chamber past the front edge of the gasket fire ring as that usually causes gasket failure
gasketsh.png


fel-hs7733pt9_xl.jpg

fel-hs7733pt9_xl.jpg

the stock 1986-91 tpi head gasket FELPRO HS7733pt9

http://garage.grumpysperformance.co...oving-gaskets-the-wrong-way.10464/#post-43962

http://garage.grumpysperformance.com/index.php?threads/head-gasket-related.1859/#post-50617

http://garage.grumpysperformance.com/index.php?threads/which-sealant-goes-where.700/#post-43768

http://garage.grumpysperformance.com/index.php?threads/sbc-head-gasket-choice.11070/#post-49297
RELATED INFO...now RICKS doing it on HIS T-bucket..so far, no problems either??

viewtopic.php?f=69&t=3814&start=608

viewtopic.php?f=52&t=4403&p=26316&hilit=copper+gaskets#p26316
 
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Unless your using 15.0-18:0. :1 static compression ratio, 500-750Hp shots of Nitrous Oxide, Super Charger & Turbo boost power adder of 500-1500 Hp there is no need to O-ring the block or heads.

Copper head gaskets come from the Nitromethane Top Fuel racers.
They work and some prefer like Grumpy.

I prefer Fel Pro Race series Head gaskets.

Current trend is MLS Headgaskets.

When Nitromethane is used only O-ringing & copper headgaskets hold up without failure.
 
Fel Pro 1044 is what came off and is what I reordered. Just not enough personal or local experience using copper- was real interested in the Fel Pro 1144-53 mls, I'm not cheap but the cost certainly is a factor when I don't feel that I really need mls and the fact that feedback on them is a little spotty- with nothing bad heard about the 1044. I do realize that of the 1000's sold- not all with fall into competent hands- I also know that the surfaces weren't finished with mls in mind although the 1144 are supposed to be more forgiving than others.
 
I may try copper head gaskets down the road.
SCE makes them for Pontiac V8's.
 
Fel Pro 1016's Pontiac V8 Racing headgaskets haven't ever failed me.
What I am using again in 2015.
 
As published in AERA Magazine by Ryan Hunter, President, SCE Gaskets, Inc.

Let’s dig into it because there are applications (perhaps more than you think) for which copper head gaskets are the best choice. To be sure, copper has been around for a while and with good reason. Let’s walk through some of the attributes and benefits unique to copper, then we’ll get ready to put them on.

Malleable: Copper is stronger than any composite head gasket yet still malleable so it conforms to the sealing surfaces. This strength-malleability combination is, more than any other attribute, the ‘selling point’ of copper as a head gasket material over other materials. While the advantages of strength are self evident, the benefits of a malleable gasket body are somewhat more nuanced. Simply put; conformity makes a tighter seal which will show up in lower leak down percentages.

Metal-to-Metal: To an engine builder, the words “High Performance” pre-suppose high pressure, high pressure requires a more robust combustion seal and the best combustion seal is metal-to-metal. I’ll elaborate; many cylinder head gaskets are coated with sealants designed to eliminate fluid leaks. From experience, readers of this article will be familiar with the various types from slick to sticky and while these work well for fluid sealing they are not able to withstand combustion pressure and heat. No matter how good an elastomeric coating may be for coolant or oil, it will eventually scrub off, burn off, or blow off the fire ring area of the head gasket and in performance engines this can happen in a surprisingly short period of time. Once the sealant is gone from the fire ring combustion seal it’s a short trip to the nearest coolant passage. Silicone, or other rubber-like sealants or coatings should never be placed on the combustion seal in performance engines.

Options: Copper comes in a wide range of thickness choices; (from .021” to .093” in roughly ten thousandths increments) providing the options necessary to optimize piston to valve, piston to head and in wedge combustion chambers, piston to quench area.

Conductivity: Copper is the standard for conductors, in head gaskets we don’t care about electricity but we do deal with heat. Superior conductivity benefits performance and racing engine builders in two primary ways: A. block & head temperatures are more even. B. Combustion chamber hot spots are dissipated quickly. Cylinder block/head temperature parity is an aid to tuning, though frankly, it’s a minimal factor until you reach the narrow end of the tuning window. The big advantage of conductivity is in the combustion chamber area. In and around the combustion chamber standard composite head gaskets and MLS head gaskets are somewhat insulated from the cylinder head and block by the facings and coatings respectively. Heat related failures occur more often with composite and MLS head gaskets than with copper because the heat is trapped within the gasket body allowing hot spots to intensify, whereas the copper being both a better conductor and having direct contact with the block and head (remember metal-to-metal) transfers the heat to the heat exchanger, aka the cooling system, through the head and block.

Elasticity: Another interesting feature of copper, this benefit comes into play when you’re out of the tuning window far enough to actually damage the head gasket. Un-alloyed or pure copper has a 25% coefficient of elasticity; cool term, here’s what it means. In a 4 inch section, the copper head gasket will stretch to 5 inches before it ruptures. This gives the user a ‘safety factor’ not available with other head gasket materials. Blown, nitrous or turbocharged engines can develop cylinder pressures high enough to lift the cylinder head or push the gasket. A typical bad-actor in this regard is the small block Ford; get some good cylinder heads, add some boost or nitrous, she’s goin’ fast but Daddy wants more and.. the head gasket is peekin’ out between the bolts. If this happens with copper the damage is apparent but the head gasket hasn’t yet failed. The safety factor of elasticity allowed the copper gasket to push but still remain intact so you can either back it down & make the next round or back it down & drive home. If you push a composite gasket, game over.

Do Copper Head Gaskets Require Different Torque Values?
Generally No. Fastener torque values are determined in relationship with the cylinder head and block structure. Arbitrarily increasing torque values will distort the block or head. However, there are good cases for fine tuning the torque values based upon how the head gaskets look after the first use. A nice thing about copper head gaskets is that you can ‘read’ them very easily once you know what to look for and, what to look for is evenly distributed clamp load. No gasket works in isolation, all gaskets require clamp load to do what they do and copper gaskets tell you where the clamp load is light by keeping their shine. Specifically, you want to see machining marks from the block & head surfaces transferred to the copper gasket body everywhere on the gasket. Places where the original finish of the gasket remains need some attention. Keep in mind there may be other factors in play such as, a ring dowel counterbore that has become too shallow from surfacing or a head nut bottoming on the threads of a head stud. Once you have eliminated any mechanical obstruction preventing the head from seating properly you can safely increase torque values in the light load areas by 5 to 10 ft lbs.

What about re-torquing? Solid copper (like a liquid) does not compress, it displaces. Since the copper gasket body does not compress no re-torque is technically necessary. However, since the engine build using a copper head gasket is almost always within the realm of performance or racing, I always recommend one re-torque of the head bolts after a complete heat cycle.

Block & Head Preparation for Copper Head Gaskets:
Cleanliness is next to..You might be surprised at some of the samples we’ve received from customers asking “why did it fail?” Then again if you’ve been around for a while, you may not be surprised at all. I have seen head gaskets with sawdust, sand and actual small rocks embedded in them, as well as the remains of facing material from the previous head gasket. The aircraft industry has an acronym that’s suitable here; FOD, Foreign Object Damage. Like leaving a wrench in the lifter valley, rocks in the combustion seal are not ok, chaos will ensue. So, as Momma taught us: let’s be clean when we’re doin’ our duty. Use a residue-free solvent such as aerosol brake cleaner and a clean rag on the head and block sealing surfaces before assembly.

Flat: Of course the block & head should be flat within .002” across and .004” lengthwise, with surface finish of 60 to 80RA preferred, 60 to 100RA acceptable.

Combustion Sealing: Head gasket sealing is a matter of balance and more pressure is needed on the combustion seal than other areas of the gasket, this is due to the vast difference in pressures acting against the head gasket. Consider that an engine developing 1.5 to 2 horsepower per cubic inch will have between 1000 and 1200 psi in the combustion chamber while, less than 1/2” away, the cooling system is running at 22psi max. Since a standard copper gasket is flat, clamp load from the tightened head bolts will be distributed evenly unless some method is used to ‘tip the balance’ and concentrate the proper load on the combustion sealing area. When using flat copper head gaskets, the accepted method has been to install O-rings in the block or head sealing surface around the bore or chamber respectively, to accept an o-ring. What’s an o-ring you ask? Simpler than you think, it’s just a piece of wire tapped into a groove that sticks out enough to pinch the copper gasket. Well, maybe that’s an over simplification but all you have to know from there are the proper dimensions of the O-ring groove.

Sealants Required? Yes, some method of sealing is required if the engine will be running coolant or oil through the head gasket. I state it this way because many racing specific engines either A. do not run coolant or B. re-route the coolant and oil away from the head/block mating surfaces. Since most engines run coolant and oil through the head gaskets we’ll discuss head gasket sealants. Most importantly, you don’t need very much; second, don’t use silicone.. that about covers it. People get into trouble with leaking head gaskets when they use too much sealant, especially too much silicone. Since the block and head surfaces are flat, the potential leak paths are very small, even with a 100RA surface finish the peaks and valleys are only about .002”, which doesn’t require very much sealant to be fluid-tight. Head gasket dressings do not cure, therefore, as the head bolts are tightened the sealant ‘flows’ from the places it’s not needed (peaks) but remains in place to seal the leak paths (valleys). By contrast, silicone cures to form a layer that the cylinder head can sit on, never actually coming into contact with the head gasket (refer back to our discussion about metal-to-metal above). We recommend and use both KW Copper Coat and Hylomar in the aerosol cans, simply spray a light coat on both sides of the gasket, let it ‘tack up’ for a while (no less than 15 minutes) re-spray a second coat on both sides just before installation and you’re ready to bolt the heads on.

We could go into much more detail about each of these items if this was a technical manual but my hope is that this information will be of help to you when the need arises, or you need some options that are not available from conventional head gaskets.

SCE Gaskets manufactures a complete line of racing and performance gaskets including standard flat copper head gaskets of the type discussed here. As well, we offer our patented self sealing (no sealant required) copper head gaskets for use with O-rings and self sealing copper head gaskets with Integral Combustion Seal O-rings (no machining required). We also have a complete line of replacement gaskets for passenger cars, light trucks, vintage and tractor engines marketed under our Engine Master brand

http://garage.grumpysperformance.com/index.php?threads/torque-to-yeild-head-bolts.2138/#post-5763
 
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Grumpy, when I purchased the solid copper head gaskets you suggested ,
I took them out of the package and briefly examined them, then put them back on the shelf.
Now I open the package almost a year later and I'm ready to use them and they have very obvious finger prints that won,t easily clean off with solvents like gas, or alcohol,
these gaskets cost over $100 a set are they ruined?

NO THEY WILL BE FINE IF CLEANED< FINGER PRINTS AND ALL>

as usual Ill take a great deal of crap over this suggestion, but why not run a solid copper head gasket, they are re-usable, and while rather expensive Ive had very good luck and consistent results, no leaks etc, and no I did not use the grooved heads and block or embedded wires
ask RICK, hes using a set, and no thats not the way they suggest, but in 30 plus years I never had one fail

1 800-GASKET-0 (427-5380)

www.scegaskets.com

SCE Gaskets - Delivering Horsepower

SCE Gaskets home, where you can find Catalogs, Tech Tips, Recommendations, Installation Instructions & Videos, Dealer Locator, On-line Shopping
www.scegaskets.com
www.scegaskets.com

1986 iron head l98 corvette valve spring question

Always ran 91 in it Yeah, you are right, that bring your SCR/DCR to 7.38/9.58. That's why I always ask the person to review my numbers when I do a simulation. What octane gas are you planning to use?
garage.grumpysperformance.com

SBC Head Gasket choice.

In a previous life the block was 0 decked then stroked to 383 and now the pistons sit out of the hole .015in, bore is 4.040in. Looking at readily available stock. Block wasn't particularly finished for MLS, heads Alum afr. Cometic isn't a choice. Daily driver. GMPP is the tightest at 4.100in...
garage.grumpysperformance.com
they come in lots of bore size and thickness from .021-.092 at about roughly every .0100 step
www.scegaskets.com

Pro Copper Head Gaskets for SBC: P11202 | SCE Gaskets - Premium Engine Gaskets

Pro Copper Head Gaskets for Chevrolet Small Block Bore Opening: 4.200" Gasket Thickness: .021"
www.scegaskets.com
www.scegaskets.com
www.scegaskets.com

Pro Copper Head Gaskets for SBC: P11152 | SCE Gaskets - Premium Engine Gaskets

Pro Copper Head Gaskets for Chevrolet Small Block Bore Opening: 4.160" Gasket Thickness: .021"
www.scegaskets.com
www.scegaskets.com


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It might be a surprise to many guys but a $10, METAL CARPENTERS SQUARE can be used , to verify a block thats is significantly warped on the deck surface
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http://garage.grumpysperformance.com/index.php?threads/sbc-head-gasket-choice.11070/#post-71671

http://www.themechanicdoctor.com/replacing-faulty-head-gasket-ultimate-guide/

http://www.jegs.com/i/SCE-Gaskets/829/T ... tId=753475
829-T11066.jpg

copper head gaskets come in several designs, the embossed version above is fairly common and used like most other head gaskets

the solid copper head gasket is generally used with wire o-rings in the block, but Ive used them for decades with zero problems without the wire o-rings


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copperh1.jpg

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http://scegaskets.com/store/chevrolet/chev-sbc/sbc-head-gaskets/sce-gaskets-part-number-p11062/

you don,t really have a serious issue, its only cosmetic not structural damage,
and if its de-greased and cleaned, and sprayed with copper coat spray,
it will work fine even if the visual discoloration partially remains.
but in the future it helps to spray copper head gaskets with WD40 on both sides if they are to be stored.
most peoples finger tips have a bit of both moisture and acid and clean and dry copper head gaskets will etch or dis-color if left un-coated.
if your concerned a paper towel and a bit of TARNEX (sold at most hardware stores and home depot) will remove the discoloration
.
tarnex.JPG

most guys that use copper head gaskets use O-RINGED heads , and while thats a good idea if you intend to use a turbo or heavy nitrous loads,
on the engine.
I have never yet found its required, on a N/A or even up to 250 hp nitrous engine combo, if you simply spray both sides of the copper head gasket with two coats of COPPER COAT spray,
copperspray1.jpg

and install the head gaskets while the coating is still a bit tacky (damp), obviously the head and block surfaces must be totally clean and de-greased and cleaned with a solvent that leave zero residue,
(toluene followed by alcohol, on lint free rags)
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prior to head gaskets installed.
remember the head bolt threads should be dipped in sealant,
on any block where then extend into the coolant passages
http://garage.grumpysperformance.co...eventing-leaky-head-bolts-studs.50/#post-1253

http://garage.grumpysperformance.co...ping-bolts-and-studs-coolant-free.15/#post-21

many guys like to use a small bit of the copper silicone high heat sealant placed around the intake manifold coolant passages in the intake gasket
copseal1.jpg


https://www.enginebuildermag.com/20...avoid-when-resurfacing-cylinder-heads-blocks/
Resurfacing Cylinder Heads & Blocks? Mistakes to Avoid
AuthorLarryCarl_00000002216-55x55.jpg

By

Larry Carley
on

Jun 1, 2007
Cylinder heads and blocks may need to be resurfaced to restore flatness or to improve the surface finish, or milled to change the deck height for a variety of reasons.

The deck surface on the head or block may need to be resurfaced if the surface isn’t smooth or flat. A head may need to be resurfaced after welds or other repairs have been made, or milled to increase the compression ratio. The manifold surfaces on a head may need to be cleaned up due to corrosion or erosion, or the angle changed slightly to better align with an aftermarket intake manifold. The deck surface on the block may need to be resurfaced. Whatever the reason is for resurfacing these parts, you want to do it quickly, efficiently and correctly. Mistakes here can be very expensive, because once metal has been removed there is no putting it back.

Misalignment

Before you can resurface or mill a cylinder head or block, you have to square it up with your resurfacing equipment. You can’t just plunk a head or block onto a fixture, clamp it down and start cutting. You have to line it up so the surface is parallel with the cutter head fore-and-aft, and side-to-side. Once you’ve accomplished that you can set your depth of cut and proceed with a rough cut or finish cut.

One mistake to avoid here is moving the head after you have aligned it. With some older styles of fixtures, the act of clamping down the head to make it rigid can disturb the alignment. The fixturing on some newer machines allows you to make the part rigid, then align it before you cut it. One resurfacing machine also has an indicator gauge on the rail that makes set up quicker and easier for accurate resurfacing.

You also want the part (and the resurfacer) to be as rigid as possible, with no movement while it is being resurfaced. Any movement will affect the surface finish.

Wrong Surface Finish

To seal properly, a head gasket requires a surface finish that is within a recommended range. The specifications vary depending on the type of head gasket. If the surface is too rough, or in some cases too smooth, the gasket may not seal properly and leak or fail. One common mistake to avoid here is not looking up the recommended specifications for a particular engine and/or a particular type of head gasket.

As a rule, the recommended surface finish for a traditional composition style soft-face head gasket in an engine with cast iron heads and block is 60 to 120 microinches Ra (roughness average). But the recommended surface finish for the same type of head gasket in an engine with an aluminum head on a cast iron block is smoother, typically 20 to 50 microinches Ra. On late model engines with multi-layer steel (MLS) head gaskets, the OEM surface finish recommendations tend to be even smoother, say 20 to 30 microinches Ra or even 7 to 15 Ra. But the aftermarket also sells MLS gaskets with special coatings for many of these same applications that can handle surface finishes in the 50 to 60 microinch Ra range. So you have to know your gaskets and the surface finish recommendations for them by the gasket manufacturer, or the OEM if you are using a factory-style replacement head gasket.

Don’t assume close enough is good enough. Eye-balling the surface finish will tell you if the surface is really smooth (a mirror-like finish), really rough (like sandpaper) or somewhere in between, but it won’t tell you if you are in the recommended range. Dragging your fingernail across the surface isn’t much better, either, because a 30 Ra finish feels almost identical to a 50 Ra finish. And the smoother the finish gets, the more difficult it is to see or feel much difference.

The only way to accurately determine if the surface finish is within the correct range is to check it with a profilometer. This is an expensive electronic instrument that drags a diamond-tipped stylus across the surface to calculate its profile characteristics. The profilometer can then display various values for the surface including roughness average (Ra), average peak height (Rpk), average valley depth (Rvk), and even waviness. These numbers may not be needed for an economy Chevy 350 rebuild, but they can be critical when building high performance engines or durability engines. The mistake to avoid here is assuming the surface finish is correct when you haven’t actually measured it.

Wrong Feed Rate/Speed

The quality and smoothness of the surface finish requires using the correct feed rate and speed for the type of tool bit. This, in turn, will vary depending on the diameter of the cutter head.

To achieve the best possible finish, you should use a higher spindle speed and lower table feed rate with a very shallow cut on the final pass (less than .001″).

If you are using a carbide insert to refinish a cast iron head, the spindle rpm required will typically be about 140 rpm for an 11-inch cutter, 120 rpm for a 13-inch cutter or 110 rpm for a 14-inch cutter.

With CBN (cubic boron nitride) or PCD (polycrystaline diamond) inserts, the recommended spindle speeds are much higher: 1040 rpm for a 11-inch cutter, 880 rpm for 13-inch cutter, or 720 rpm for a 14-inch cutter. If the head or block being resurfaced is harder, high silicon content alloy, the speeds need to be slowed down a bit: 690 rpm for a 11-inch cutter, 580 rpm for a 13-inch cutter or 540 rpm for a 14-inch cutter.

With a single CBN or PCD insert cutter spinning at 1,000 to 1,500 rpm, the feed rate should probably be less than two inches per minute on the final cut to achieve a surface finish in the low teens.

Removing Gaskets The Wrong Way

Engine disassembly is a dirty, greasy, time-consuming job, so any shortcut that makes the work go faster is a good idea, right? Maybe not if the short cut ends up damaging parts or creating more work for you in the long run.

The practice we’re talking about here is using an abrasive pad in a drill to grind off gasket residue that may be stuck to the heads or block. The abrasive will certainly whiz the gasket debris right off, but it can also whiz off metal leaving a shallow depression, a dig or a groove that may create a sealing problem when the engine is put back together.

Another reason not to use an abrasive disk to grind off or clean a surface is that it generates a lot of dust. Some gasket fibers may be hazardous to breathe. A dust mask can protect your lungs, but the residue can end up in other places where it may cause problems later (like in the cylinders, intake ports, oil or coolant passages).

The best way to remove gaskets is with a sharp scraper and/or a can of aerosol chemical gasket remover. Spraying the gaskets with a chemical remover eliminates hard scraping and the risk of scratching or gouging the surface, especially on soft aluminum heads and blocks. The chemical does most of the work by softening the gaskets. The residue can then be easily scraped off the surface.

One mistake to avoid here is using the wrong tool to scrape off the gaskets. An old screw driver is not a gasket remover. Nor is a putty knife. A gasket scraper is the right tool to use because it has a sharp, beveled edge that gets under and lifts the old gasket from the surface. Just make sure the scraper is sharp (it should be sharp enough to cut paper).

The trick to using a gasket scraper correctly is to scrape at an angle that is almost parallel to the surface. By keeping the angle small, the tip of the scraper will slip under the gasket and shear it away from the surface without digging in. If you try to use it like a chisel, you’ll probably end up gouging the surface and damaging the surface. Also, hold the scraper so you push it forward (away from you) as you scrape. This way, if the tool slips it won’t gouge you.

Not Checking Flatness

Never assume a head is flat. You can’t tell if a head or block is flat or not unless you measure it with a straight edge and feeler gauge. You should always check for flatness, especially in critical areas like those between the cylinders.

Flatness specifications vary depending on the application, but on most pushrod engines with cast iron heads, up to .003″ (0.076 mm) out-of-flat lengthwise in V6 heads, .004″ (0.102 mm) in four cylinder or V8 heads, and .006″ (0.152 mm) in straight six cylinder heads is considered acceptable. Aluminum heads, on the other hand, should have no more than .002″ (.05 mm) out-of-flat in any direction. On a performance engine, the flatter the better.

If the face of an aluminum head is warped, don’t assume the only way to straighten it is to grind metal off the face until it is flat again. The whole head is warped. If the head has one or two overhead camshafts, the cam bores will also be misaligned in most cases. The best fix here is to straighten the head BEFORE it is resurfaced. This can greatly reduce or possibly even eliminate the need to remove more than a couple thousandths of metal.

Aluminum heads can be straightened by countershimming the head on a heavy steel plate (place shims under either end of the head to offset the amount of distortion), clamping it down, then heating it in an oven to about 425° F for several hours, then letting it slow cool. The goal is to get the cam bores straight. Once they are in alignment, chances are the face of the head will be reasonably flat, too, and require minimal machining to refinish the surface.

Another method for straightening aluminum heads is to use a torch to head the top of the head, starting in the center and working towards the ends. The trick here is to keep the head temperature under 500° F to prevent softening the head too much.

Taking Too Much Metal

A head or block with a depression in the surface, or a surface that is out-of-flat can be made flat again by simply increasing the depth of cut when the part is resurfaced. The rule here is to always remove the LEAST amount of metal that’s necessary to restore flatness. Remove too much metal and you could end up with problems.

Excessive milling reduces the volume of the combustion chambers and increases compression, possibly to the point where detonation may become an issue even with higher octane fuel. On overhead cam engines, milling too much metal off the face of the head changes the installed height of the head and retards cam timing. On a pushrod head, it will alter the valvetrain geometry and may require corrections in the length of the pushrods. The only way to restore lost head height and combustion chamber volume is to use a copper or steel head shim with the head gasket, or replace the head.

Don’t ‘Make Do’ With Outdated Equipment

Extremely smooth finishes require high quality resurfacing equipment (typically a milling machine) to achieve really low Ra numbers. It doesn’t matter if you use carbide, CBN or PCD tool bits to resurface a head as long as you use the correct feed rate and speed – and the equipment is rigid enough to hold the cutter steady so the tool bit doesn’t lift or chatter when it makes in interrupted cut.

For example, a converted grinder may be able to mill heads and blocks. But the spindles and table drives in many of these older machines cannot hold close enough tolerances to achieve a really smooth, flat finish. One equipment manufacturer said grinding and milling machines that are more than five years old are probably incapable of producing consistent results and should be replaced.

Most of the surfacing equipment that’s being sold to shops today has been redesigned for high speed milling with CBN and PCD. The machines have been beefed up with more powerful motors, heavier castings, electrically-driven ball screw tables, and tighter assembly tolerances. Some can hold machining tolerances to one tenth of a thousandth of an inch (.0001″)!

Using The Wrong Tools

Though the experts recommend using PCD on aluminum and CBN on cast iron, many shops find CBN works fine on both types of metals and eliminates the need to change tooling when resurfacing different types of heads.

CBN may not be the best choice for milling aluminum because aluminum tends to stick to CBN and leave a smeared finish. Even so, there is a way to prevent this from happening: just spray a lubricant on the surface or the cutter. According to one source, the absolute best lubricant to use for this purpose is olive oil. Only a little is needed, and it’s non-toxic, doesn’t stink and is relatively inexpensive.

PCD works better on aluminum than CBN (and costs about the same), but PCD is not recommended for resurfacing cast iron heads or blocks because diamond gets too hot at high cutting speeds, reacts chemically with iron and breaks down. CBN can handle higher temperatures than PCD, and dissipates heat about four times faster than silicon carbide or aluminum oxide, making it a good choice for high speed resurfacing.

Something else that must be considered when using CBN to resurface heads and blocks is the depth of cut. CBN inserts typically have a honed edge, so the minimum depth of cut is usually limited to about .004″ or .005″ on cast iron. If too shallow a cut is attempted, the result can be edge deterioration, poor tool life or chipping of the insert (CBN is sometimes coated with titanium to improve tool life).

Trying To Get Too Much From A Bit

CBN and PCD last a lot longer than carbide, but they don’t last forever. One common mistake that’s made is trying to cut too many heads or blocks with the same edge. If you are using a CBN button for resurfacing, you should rotate the button about 5 degrees after 20 to 30 heads to maintain an optimum cutting surface.

Rotating the button just a little bit when it starts to get noisy will expose a fresh edge and reduce the risk of chipping the button or wearing it too far. Buttons with a beveled edge can be relapped to restore the edge if they are not too badly worn. But if the button has lost too much of its edge, the only option is to replace it with a new one.

Resurfacing Diesel Heads With Precombustion Chamber Cups

Here’s a job that can ruin a tool insert in seconds. The issue here is not the difference in hardness between the cylinder head and the precombustion chamber cubs, but the fact that many of these cups are slightly loose. Staking the cups won’t lock them in place because the first pass with a resurfacer will shave off the staking.

One solution is to remove the cups, resurface the head, then get the cup counterbore to the proper depth and reinstall the cups. Another solution is to make the cups rigid by applying a penetrating locking compound around the cups BEFORE you resurface the head. This saves the time and labor of removing and reinstalling the cups.

Trying To Resurface Rusty Heads

Iron oxide on a cast iron head will kill the life of a tool insert. The same goes for hard calcium deposits in water jacket openings. The cutter tool bit can also pick up this debris and drag it across the surface, leaving a groove. The mistake to avoid here is trying to resurface a dirty head that has not been properly cleaned. Remove all of the rust and calcium BEFORE the head is resurfaced. This can be done with chemical cleaners, a shot blast cleaner or a tumbler.

Not Wearing Eye Protection

Here’s another common mistake some engine builders wish they hadn’t made when resurfacing parts: not wearing eye protection. The cutter guard on a resurfacer will deflect most of the chips down, but a lot of debris still goes flying every which way while the machine is running. If you lean down to take a close look while the machine is running, you may get hit in the face with some microscopic metal shards. That’s why you want eye protection,: either a full face shield or safety glasses with side covers. You have two eyes so losing one may not leave you blind, but it will mess up your depth perception.

Lack Of Maintenance

You can’t expect to get high quality surface finishes if you’ve neglected your equipment. Dry milling doesn’t require any coolant so there’s no coolant to maintain. But the resurfacer itself needs to be set up correctly and checked periodically to make sure it is still in proper alignment.

Resurfacers need to be leveled with an accurate level. Place the level on the ways of the machine or on the table mounting surface. Adjust the machine front to back as well as left to right until it is perfectly level in all directions.

Next, check the table to make sure it is running true. Attach a magnetic dial indicator in the cutter head and traverse the left and right to see if the table is true to the wheel head. You should see no more than .002″ of variation across the entire traverse of the table. If the table is not running true, contact the equipment supplier for the correction procedure.

Also check the parallels, using a dial indicator and granite plate to make sure they are straight. If the parallels have runout, the resurfacer won’t cut straight. The cylinder head and block rollover clamps also need to be checked to make sure everything is straight.

If the cutter head has more than one tool bit, all must be set to equal height (no more than .0005″ variation) to get consistent results.




http://garage.grumpysperformance.com/index.php?threads/sbc-head-gasket-choice.11070/#post-79067

http://garage.grumpysperformance.com/index.php?threads/head-gasket-related.1859/#post-50617

http://garage.grumpysperformance.com/index.php?threads/head-gasket.10085/#post-39429

http://garage.grumpysperformance.co...ad-gasket-for-aluminum-heads.4403/#post-26317

http://garage.grumpysperformance.co...asket-bore-size-vs-bore-size.2681/#post-11603
 
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