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Old 06-03-2019, 12:45 PM   #126
impreza95
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Quote:
Originally Posted by bp05obxt View Post
There are two different setups with the composite gaskets. The first is the original Athena gaskets using Cooper rings that require nothing to be modified on the deck surface. IAG has a Fire-Lock gasket which is an evolution of the original and requires the deck to be modified for their changes.


In short Athena gaskets/cooper ring gaskets are the best performing head gaskets until a certain power level. That power level isnít specific to one number and is reliant on what the car is setup and driven for; how it is tuned; and various other variables. What can be said however is that the IAG Fire-Lock increases failure point significantly nearly to non-failure if done so correctly.


Side note:
Important for anyone using either of these options; make sure the rings that seal around the cylinders have the grooves sides facing up/outward towards the heads so that they can bite into the cylinder head when torqued. This has become all to common mistake and ensures that head gaskets will fail prematurely if the rings are not installed correctly.
Thanks the ones I'm using are the ones that don't need machined I was panicking when I started reading all this thinking some how we missed that part thanks for cleaning it up.
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Old 06-15-2019, 12:35 PM   #127
Rideit636
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Any updates on these as far as reliablity? I'm on 11mm 625+ and Cosworth gaskets. Starting to push coolant at 37-38psi. These seem like my only option.
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Old 06-15-2019, 01:13 PM   #128
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Originally Posted by Rideit636 View Post
Any updates on these as far as reliablity? I'm on 11mm 625+ and Cosworth gaskets. Starting to push coolant at 37-38psi. These seem like my only option.
14mm studs, RCM stopper gaskets and a CDB will handle that easily enough

The Athena gaskets.....still need more convincing of them....plus the fact they do bite into both the head and alloy block deck. So really not a solution for all.

Strangely on other engine platforms I've seem people posting pictures of deformed and blown out rings, which must take some effort, or else there are still bugs with the setup
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Old 06-15-2019, 01:29 PM   #129
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IAG firelock and 14mm head studs are the best out there at the current moment. It is a further development of Athenaís cooper rings.

I fail to see how RCM gaskets are any different then any other MLS gaskets. They may very well be the best MLS gaskets, but far less capable then the IAG firelock set up.
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Old 06-15-2019, 02:01 PM   #130
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Originally Posted by bp05obxt View Post
IAG firelock and 14mm head studs are the best out there at the current moment. It is a further development of Athenaís cooper rings.

I fail to see how RCM gaskets are any different then any other MLS gaskets. They may very well be the best MLS gaskets, but far less capable then the IAG firelock set up.
And from their website...their Firelock requires block machining. Not so practical for all.

And to ask why RCM stopper gaskets are any different than any other MLS....would suggest you've never actually seen an MLS gasket, given there are literally dozens of configurations and designs across all makes, whether it be layers, coatings, thicknesses, fire rings or not etc etc etc. There may even be hundreds of variations.

One would ask why IAG deemed the need for the block machining for their ring setup....although finding a secure base for the ring would seem a possibility rather than it sitting on the Alu block.
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Old 06-15-2019, 02:44 PM   #131
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Originally Posted by Rideit636 View Post
Any updates on these as far as reliablity? I'm on 11mm 625+ and Cosworth gaskets. Starting to push coolant at 37-38psi. These seem like my only option.
Which turbo are you using?
And what is youre power/tq level?
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Old 06-15-2019, 06:40 PM   #132
bp05obxt
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Default New composite head gasket. Anyone using it?

The reason for block machining was to accept the IAG firelock head gaskets which is the step beyond Athena cooper rings. The Firelock came about due to Athena cooper ring failures, also mentioned earlier, at increased power levels. Hence why the Firelock is capable of 1000whp+.

Block machining isnít convenient but it is the best bet for avoiding head gasket failures.
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Old 06-17-2019, 09:02 PM   #133
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Which turbo are you using?
And what is youre power/tq level?
Gen2 GTX3576. Enough to trap 135 in a full weight 15 STI Limited. 600-700 depending on who's dyno it's on. I pulled the trigger on some JE ProSeal that I'll toss in this weekend. I don't like the fact that these leave an impression in the heads and the potential for FUBAR head and block surfaces in the event of another headgasket failure.
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Old 06-17-2019, 09:14 PM   #134
Long Nguyen
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I have used these Athena gaskets with COOPER rings (I guess the former version) on my 2 high power engine builds. Both make ~770whp at 40psi of boost. No problems so far (about 5k miles).

However, these are street driven hence not under huge stress in race condition.

The timing at full boost up top is healthy 17-18 degrees on E85.

And I believe timing plays a huge part in longevity of head gaskets.

The studs are 1/2 from Outfront torqued to 115ftlb for outer studs and 125ftlb inner studs. I did not machine the grooves on block side (as instructed not to by Outfront)

I do have a set of dummy gaskets for torque plate honing. These cooper rings will distort the cylinders much.

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Old 06-17-2019, 11:00 PM   #135
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Quote:
Originally Posted by Long Nguyen View Post
I have used these Athena gaskets with COOPER rings (I guess the former version) on my 2 high power engine builds. Both make ~770whp at 40psi of boost. No problems so far (about 5k miles).

However, these are street driven hence not under huge stress in race condition.

The timing at full boost up top is healthy 17-18 degrees on E85.

And I believe timing plays a huge part in longevity of head gaskets.

The studs are 1/2 from Outfront torqued to 115ftlb for outer studs and 125ftlb inner studs. I did not machine the grooves on block side (as instructed not to by Outfront)

I do have a set of dummy gaskets for torque plate honing. These cooper rings will distort the cylinders much.



This is what should be highlighted here. Well built and well tuned; absolute necessities for a reliable engine build. It should be obvious but people so often push things so far and hard that the engines fail before they have any chance. Cooper ring Athena gaskets with 1/2 or 14mm head studs really are the best bet before machining the block is necessary. It should also be noted incorrectly installing Cooper rings has been the cause to numerous failures; it is amazing how many people canít install something so simple incorrectly.
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Old 06-18-2019, 09:51 PM   #136
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Seems like for the hassle of these in between gaskets, people would just sleeve and machine for stainless O-rings and use some JE pro seals and get it over with. I've seen many setups making 600whp with no "fire rings" or "cooper rings" or any special rings...just quality head gaskets, quality designed builds, and quality tune.

Obviously the close deck converted blocks are capable even without special headgaskets, but if you're possibly going past what the close deck can handle and getting into these gaskets that bite into the head and/or oem sleeve, it would seem you've passed the point of oem sleeves and starting to get into the possibility of distorting the oem sleeves and necessitating running aftermarket sleeves.

Just too many menu choices in my opinion, lol!
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