Head Gasket experts...check in....

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I'd check the rod bearings, piston crowns, and plug porcelain for signs of detonation. You "shouldn't" be having that issue with studs IMO. What is the cylinder pressure, and what fuel are you running?
 
In the ARP catalog, the head stud section lists them as being either 200,000 or 220,000 psi.

The “recommended torque to achieve optimum preload(clamping force) using ARP lube”......
For a 200,000psi 1/2” fastener is 125ft/lbs.
If you use motor oil, the tq value should be higher.
I don’t feel the new ARP lube(in the blue packets) allows for as much stretch with the same tq value as the older lube did.

I don’t know if something has changed with the current crop of ARP head studs as compared to what they were 20+ years ago...... but back then the tq spec for using 30w oil instead of the ARP lube was 140ft/lbs.
No problems at all with my Dads old 13:1 360 doing it that way with factory 596 heads.

You could probably knock it down a little because of the higher expansion rate of the aluminum heads.
 
compression is 11.8 to 1....fuel is E85.....studs were torqued down to 105 with arp lube...

pistons...valves...all look good....
 
70aarcuda said:
compression is 11.8 to 1....fuel is E85.....studs were torqued down to 105 with arp lube...

pistons...valves...all look good....
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Maybe try a cometic with some
Hylomar around the water passages and bump up the torque on the studs.
 
From what I can tell from the pics, it doesn’t look like heat burned through the fire ring.
It looks like the fire ring wasn’t holding a seal, and the escaping combustion gasses torched the paper/rubber part of gasket that’s out past the fire ring.

It’s a common area for a SB Mopar head gasket to fail since it doesn’t have a lot of area to be squeezed between the block and head, so it doesn’t have a very good way to transfer/dissipate the heat out of the gasket body into the block and heads.
The material the Cometics are made of will be able to withstand the higher temps better.

Fundamentally, I think it’s likely a tune up issue.
Whether that’s from a faulty timing light, weak fuel pump, bad batch of fuel, etc..... who knows.
But I think a Cometic would have a better chance of surviving it.
 
PRH said:
From what I can tell from the pics, it doesn’t look like heat burned through the fire ring.
It looks like the fire ring wasn’t holding a seal, and the escaping combustion gasses torched the paper/rubber part of gasket that’s out past the fire ring.

It’s a common area for a SB Mopar head gasket to fail since it doesn’t have a lot of area to be squeezed between the block and head, so it doesn’t have a very good way to transfer/dissipate the heat out of the gasket body into the block and heads.
The material the Cometics are made of will be able to withstand the higher temps better.

Fundamentally, I think it’s likely a tune up issue.
Whether that’s from a faulty timing light, weak fuel pump, bad batch of fuel, etc..... who knows.
But I think a Cometic would have a better chance of surviving it.
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Cylinders 3&5 are also the cylinders with the side by side exhaust valves so that part of the head and block is hotter.
 
Might have got pushed out if it hydrauliced if any water got in those cylinders
 
I just pulled some1008s off of my 340 and it didn't take much to crack them loose and I know I torqued them sons of bitches with a trustee torque wrench. I'm "thinkin" about them. Then I see this thread.

They come with a steel ring in them.
My 8553 pt did fine at 188psi . Hmmm
 
I don't know anything about E85, except what I heard, and that is,
that it can take a lot of abuse without detonating. And with a little detective work, I'm guessing OP is running a big-enough cam that the cylinder pressure is not a big deal. At 11.8 @2000ft elevation,and an ICA of say 68* the pressure might already be down around 185psi. That Ica of 68* is a small cam for a 410, like a 284 or maybe a 292

So that kindof points to a mechanical issue, such as too smooth surfaces?
But because every one went to the inboard side, I'm wondering about the intake fit.
 
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70aarcuda said:
Head gasket removed from 410 engine ....cylinder 3 and 5 show the gasket egg shaped...cylinder 1 the fire ring was detached from gasket.....any clues?

engine is flat top zero deck 410 cubic inches...with ARP studs....close chamber eddy heads...

View attachment 1715309317

View attachment 1715309318
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Here is a link to a custom cometic head gasket that I had made and anyone can buy.
My thoughts were that is would better cool in the centre of the heads. No extra cost to buy if you are interested. The part number is in one of the pics.Custom Cometic head gasket pics
 
AJ/FormS said:
Unless OP has massive dynamic cylinder pressure, Ima thinking that this is a massive pressure issue from some other source, such as preignition/ detonation, and 140 ftlbs isn't gonna solve this gasket problem.
While 34* power-timing sounds about right, if perhaps 2* high for the Eddies, mine does not arrive until 3400 rpm. In this way I can burn 87E10 full-time, and my engine has never burned anything else, at the aforementioned 185psi.
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AJ/FormS said:
Unless OP has massive dynamic cylinder pressure, Ima thinking that this is a massive pressure issue from some other source, such as preignition/ detonation, and 140 ftlbs isn't gonna solve this gasket problem.
While 34* power-timing sounds about right, if perhaps 2* high for the Eddies, mine does not arrive until 3400 rpm. In this way I can burn 87E10 full-time, and my engine has never burned anything else, at the aforementioned 185psi.
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Not to discount your comments here, but the sbm has always had trouble with head gaskets at very high compression ratios around the 12:1 point.
The main reason is its design of only 4 bolts around each cylinder. That is why the R blocks have a provision for 6 bolts.
The 1008 gasket was the only gasket for the sbm that would work, but it too can still have trouble. The Mls cometic is now the go to gasket if the ratio calls for it. 11.8 to 1 is pushing it limits.
 
70aarcuda said:
hughes 264/268 -108 ....installed at 104
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Well that will drive your pressure right thru the roof. With an Ica of 55*, Mr. Wallace says 210 psi. That counts as massive for pumpgas; IDK for E85; but the 1008s sure seem to be overwhelmed.

EDIT;Or is that at .050 ?
 
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thanks everyone.....everything is cleaned and ready to go back together....due to time constraints...I am going to use the 1008 head gasket again....and address the problem later this year....
 
Summit has both .027 and .040 Cometics in stock that you could have in 2 days (Tomorrow if you drive there)
Screenshot_20190326-204800_Samsung Internet.jpg
 
ok... forget the drive. 7hrs..lol
But if you left now you would be home by noon...hehehe
 
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