Copper head gasket????

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volaredon

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Just throwing it out there for ***** and giggles.
When I ported my head I just barely went to clean up the edges of the combustion chambers especially the jagged edge around the intake valves, and I set a HG on the head and it seems I should have left it alone, as now the chamber edge won't cover the fire ring on a stock style replacement HG. I'm probably less than 1/4 of the way into the fire ring, but that sliver that sticks out past the chamber bugs me, even though it's plenty big enough to clear the edges of the cylinder bore. I came up with an Aussie HG from a buddy of mine from the slant 6 site and when I asked "how much" he said "just get me another one, don't have to be in a hurry" well, if I can convince myself that a stock replacement will be fine, or possibly get me a copper one I can give this one back.
I'm looking at daily driver just under 9:1 so I know that considering that copper would be unnecessary, but just thought I'd ask about the idea anyway

While we are on the subject just like the brass freeze plugs idea, the copper should be more corrosion resistant by the water jackets as well, right?
How thick are typical copper head gaskets for a slant? This isn't something that I plan to tear apart very often once assembled and running. One reason I don't want to run the Aussie one is the extra thickness. Between the head and block I have had 100 thou shaved. 30 off the block and 70 off the head. I'm thinking that I should have reversed those numbers but what's done is done and that's how it's gonna be. And another story, besides
 
No part of the fire-ring can be proud in-chamber, it'll burn thru, get a larger bore gasket......what You choose is up to You.....& Your deck ht.
 
.org had a run set up not that long ago for some copper, which can be any gauge available the dies can cut /emboss accurately.
 
Just curious, why copper? Also, I've seen those supposed Aussie "big bore" gaskets. They advertise 3.6" but I've measured several stock gaskets I have here at 3.55 and 3.56, so I'm wondering what the bruhaha is all about. Can you post some pictures of the gasket on the head or block?
 
I've measured the fire ring dia (and had a post on it her a while back with not much activity) of a few different brands, and the Aussie clears while fel pro, an nos shim steel one, ROL, and (I forget which) either McCord or Detroit gasket won't.they all clear the bore on the block side with plenty of room to spare.
It ain't much and only on 2 Chambers of the 6, but it's there.... not wanting to go with the Aussie because of the extra thickness and because if I need one later I can't just run down to road and get another/ but I have too much time and money into this head to not run it. Oversized valves, new seats on the exhaust side, lots of grinding dust and time porting, you guys know what that's about.
I had a little "stair stepping" around the intakes that I wanted to smooth out a bit on the edges, did 2 of them, and then my fel pro came in/ and I saw what I saw, so I didn't play with that edge on any more
chambers. I was surprised by how little it took, to
open them up too far. But took to eBay and bought one each of the other brands listed to compare.

And RRR this is why you now have that steel shim NOS one, and old school asbestos looking fel pro one that you do. I only had them out of the wrapping to check them with a dial caliper.
 
volaredon said:
I've measured the fire ring dia (and had a post on it her a while back with not much activity) of a few different brands, and the Aussie clears while fel pro, an nos shim steel one, ROL, and (I forget which) either McCord or Detroit gasket won't.they all clear the bore on the block side with plenty of room to spare.
It ain't much and only on 2 Chambers of the 6, but it's there.... not wanting to go with the Aussie because of the extra thickness and because if I need one later I can't just run down to road and get another/ but I have too much time and money into this head to not run it. Oversized valves, new seats on the exhaust side, lots of grinding dust and time porting, you guys know what that's about.
I had a little "stair stepping" around the intakes that I wanted to smooth out a bit on the edges, did 2 of them, and then my fel pro came in/ and I saw what I saw, so I didn't play with that edge on any more
chambers. I was surprised by how little it took, to
open them up too far. But took to eBay and bought one each of the other brands listed to compare.

And RRR this is why you now have that steel shim NOS one, and old school asbestos looking fel pro one that you do. I only had them out of the wrapping to check them with a dial caliper.
Click to expand...

I wonder if the chambers in your head are unduly big? I've not run into this with any of mine yet and I've looked. This has me wondering.
 
I dunno. I do have 2 more peanut plug heads here that I can compare head gasket fit with, but I have around $600 into this one//, more than I have put into most pairs of V8 heads over the years. And that don't count the i-don't-remember-how-many-hours that I spent porting the thing before it went to the machine shop/ nor the carbide burrs or the 2, (yeah I bought something from HF)head porting kits (sandpaper rolls) that I bought just for this job/ or the 5 hour round trip to the guy's house that has the flow bench, all hard things to put a price on.
This was my 1st honest exercise in head porting, on a head that I planned on using on a build. I've played with known cracked heads a bit, heads that I knew would never see anything but a scrap pile.
It was Magged while it was at the machine shop, I didn't hit a water jacket, and the machine shop actually went a little bit farther than I did on my porting job.
This is also my 1st time having oversized valves into a head of any kind.
So if it means I have to run an oddball head gasket and it'll work on my engine there's no going back now.
So would a copper head gasket or the Aussie one be a better bet?
 
RustyRatRod said:
I wonder if the chambers in your head are unduly big? I've not run into this with any of mine yet and I've looked. This has me wondering.
Click to expand...
He got a bit carried away deshrouding w/o scribing His gasket ring on the head, now He's got some "overhang".....
 
Killer6 said:
He got a bit carried away deshrouding w/o scribing His gasket ring on the head, now He's got some "overhang".....
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That's maybe what I was thinking. Cometic will make "whatever" you want. Unless you've opened the chambers up so far that they are larger than the bore, Cometic should be able to make a gasket that will seal.
 
There's a good chance He was unfortunate enough to have the chamber cores shifted over on a couple, not enough room even for a clean-up. It happens..like the run of 906 castings with the #3/6 cyl chamber quench cast almost .025" shallower than the rest...perscription for detonation....
 
Killer6 said:
There's a good chance He was unfortunate enough to have the chamber cores shifted over on a couple, not enough room even for a clean-up. It happens..like the run of 906 castings with the #3/6 cyl chamber quench cast almost .025" shallower than the rest...perscription for detonation....
Click to expand...
Yup. You'd figured at some point in time these manufacturers would have figured out the benefits of quench to fight detonation, but they just never did and right through the years when it would have aided them the best.

I give you the Ford 400 engine as an example. It's a tall deck Cleveland engine, beginning in 1970. The longest stroke pushrod motor Ford ever made at 4". They suffered badly from detonation for their entire run through 1982, but Ford kept going the wrong way, making piston compression heights shorter and shorter and chambers bigger and bigger and actually made the problem worse! All they would have had to do is make the chamber the same size, but make it a closed chamber, brought the piston all the way to TDC with a matching quench flat and dished the rest. Problem solved and it would have run on the crappiest gas available and probably had tire burning torque. In fact, the "should have" engine would have been the 400 short block with a reverse, quench pad, zero deck, with the closed chamber 4V Cleveland heads and a special 4V 400 intake with the big ports. That would have been ONE HELL of a truck engine. The stuff legends are made of. Oh what couldda been.
 
Yeah, Buddy had a real nice F-250, 351M. Reliable but awful, lol!
Sorry for the side-track volaredon!
 
Killer6 said:
Yeah, Buddy had a real nice F-250, 351M. Reliable but awful, lol!
Sorry for the side-track volaredon!
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Yeah I'm sorry too. Sorry about the Ford stuff. Even though I like um. lol
 
Wasn't thinking about core shift. The overhang is all on the intake side, and yes I barely did any grinding around the valves on the Chambers.
I was hoping it would shrink when I had the head shaved.
And being as how the fire ring diameter on a fel pro style replacement is 3.5-something, yet the bore size on my engine is 3.420 yeah.... I'm sure that means the Chambers are bigger than the bore size. Not ideal for sure
 
Ford's have been the one brand I have loved to hate. Now a days especially since I work as a fleet mechanic that lives them.
If I'm forced to work on them I'd rather be working on 302s 351w, 460s and the 300 straight 6.
These 4.6s and 5.4s blow ***.
More reason to own old mopars for my own transportation.
 
volaredon said:
Wasn't thinking about core shift. The overhang is all on the intake side, and yes I barely did any grinding around the valves on the Chambers.
I was hoping it would shrink when I had the head shaved.
And being as how the fire ring diameter on a fel pro style replacement is 3.5-something, yet the bore size on my engine is 3.420 yeah.... I'm sure that means the Chambers are bigger than the bore size. Not ideal for sure
Click to expand...
...and that brings up a good point. How much was the head milled?
 
volaredon said:
Ford's have been the one brand I have loved to hate. Now a days especially since I work as a fleet mechanic that lives them.
If I'm forced to work on them I'd rather be working on 302s 351w, 460s and the 300 straight 6.
These 4.6s and 5.4s blow ***.
More reason to own old mopars for my own transportation.
Click to expand...
I cannot agree more. I cannot STAND the new Ford engines. But then, I don't like anything new. Remember how modular everything was on the older ford engines? How you could just whip off a AC compressor, PS pump or anything right off the front of the old V8s? Just easy peasy. Not anymore.
 
RustyRatRod said:
...and that brings up a good point. How much was the head milled?
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I asked for 70 thou. I haven't had a chance to CC anything yet. The machine shop was leery of shaving it that much. He said when I picked it up, that he did what I asked for. He doesn't do many of these engines, so "wasnt sure" how much of a shave they would take without issue..... I told him to come here and the /6 site and see how many do 100-thou and more regularly. Once I told him that he said "oh ok, sounds like there's plenty". I was shooting for a ~48-50cc chamber when all is said and done.
The gasket alignment is about the same as before it hit the machine shop. Id like to CC it and see where I'm at..... I had asked them to do so, before they milled it... it sounded like he just pulled a number out of a book when he called me to tell me the result. I was driving at the time. When asked how much to shave off, I did a quick number crunch in my head based on that info he gave me..... and roughly 7 thou removed from the head surface for each CC of volume removed, I told him that 70 thou figure, which should have been just over 10ccs removed, from each chamber.
 
volaredon said:
I asked for 70 thou. I haven't had a chance to CC anything yet. The machine shop was leery of shaving it that much. He said when I picked it up, that he did what I asked for. He doesn't do many of these engines, so "wasnt sure" how much of a shave they would take without issue..... I told him to come here and the /6 site and see how many do 100-thou and more regularly. Once I told him that he said "oh ok, sounds like there's plenty". I was shooting for a ~48-50cc chamber when all is said and done.
The gasket alignment is about the same as before it hit the machine shop. Id like to CC it and see where I'm at..... I had asked them to do so, before they milled it... it sounded like he just pulled a number out of a book when he called me to tell me the result. I was driving at the time. When asked how much to shave off, I did a quick number crunch in my head based on that info he gave me..... and roughly 7 thou removed from the head surface for each CC of volume removed, I told him that 70 thou figure, which should have been just over 10ccs removed, from each chamber.
Click to expand...
Well, get the chambers cc'd and report back. What I was going to recommend is, maybe you can have some more milled if the static compression won't be too high. The only problem is, the stock slant 6 chamber is basically round, so it it's too big around the circumference, you'll be making little, if any difference.
 
Copper gaskets can be an option as they are available in different thicknesses depending on what the gasket company has on hand. Several Pros and Cons though, copper doesn't have any sealing qualities in itself, so it has to have sealer applied to both sides of it. Copper has a tendency to squish and then crawl around on the surface it's on because of the heating and cooling cycles than cause movement between the block and head. So o-ringing is typically required to curtail movement of the gasket over time, thus more initial cost on the front end to install. Copper gaskets can be reused numerous times, if you are careful not to mangle it up when removing it.
Probably 5 years ago or longer, I designed a copper big port intake/exhaust gasket to be used for ported heads on the Slant. Initially I sent my CAD file to SCE, and they made several batches for me, then I switched over and sent the file to have Clark begin to make them. I also designed a big bore copper head gasket for the Slant also that Clark does. They are water jet cut, whereas composition gaskets are die cut. My copper intake/exhaust gasket was used in an engine build dyno article featured in Mopar Muscle and also the same article was run in Hot Rod magazine at the same time, titled "Slant Sickness". Hopefully, those pros and cons of the copper gasket usage can help you sort out your quandry...
 
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