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Well its some time since i started this thread and after one fresh run and 1000km later the head gasket shat its self at 580 at tw and 20 lbs of boost popped out into the jackets on #6 - Tommei super grommet :) .

Not a cheap head gasket either - it never did seal well.

I do not want to strip the engine and o ring at this stage ( or should i ?) i would like to know other peoples results with other gaskets - what are the HKS and others like . I had read a few threads on other forums that a number of people had experienced probs with the same tomei gasket?

Any one offer their thoughts and experiences?

That's a pity, but it comes down to so many factors to determine the actual failure cause. I always prefer the O ring because it is hard locked into the block so you literally need something to tear in the gasket for failure. Too late now with the engine in to do the O ring, but try some of the other metal gaskets available from the online traders like Slide etc.

That's a pity, but it comes down to so many factors to determine the actual failure cause. I always prefer the O ring because it is hard locked into the block so you literally need something to tear in the gasket for failure. Too late now with the engine in to do the O ring, but try some of the other metal gaskets available from the online traders like Slide etc.

Thanks Geoff , Slide - reputable and knowledgeable ?

Shall look them up.

It's very rare for a metal gasket to fail, no matter what the brand. Check the head and block with a straightedge to see if there is any warpage, you will find that a lot of the time if the block is surface ground rather than milled it will have high areas between the bores and low areas along the sides of the bores, sometimes .002-.003". Metal gaskets need a dead flat finish, both on the head and block to seal effectively. I have seen one fail where one head dowel was left out and there was thermal walking and the gasket fretted and failed. I've seen an engine that was detonating so badly it ate away most of the quench pad on the intake side and the gasket still looked like new apart from some alloy peppered onto it around the bore.

You can run o-rings with a metal gasket, I use 1mm copper wire for anything I o-ring and it is a little easier on the gasket as it squashes a little rather than cut into the gasket. You can fit the o-rings to the head rather than the block if you dont want to strip the engine. You'd only want .006" or so protrusion if you use the steel gasket. I normally leave it .015" out for a copper gasket with a .008" receiver groove cut in the head. You will need to retension it a few times which can be a pain, especially with HKS cams without the notches to get to the head bolts easily.

It's very rare for a metal gasket to fail, no matter what the brand. Check the head and block with a straightedge to see if there is any warpage, you will find that a lot of the time if the block is surface ground rather than milled it will have high areas between the bores and low areas along the sides of the bores, sometimes .002-.003". Metal gaskets need a dead flat finish, both on the head and block to seal effectively. I have seen one fail where one head dowel was left out and there was thermal walking and the gasket fretted and failed. I've seen an engine that was detonating so badly it ate away most of the quench pad on the intake side and the gasket still looked like new apart from some alloy peppered onto it around the bore.

You can run o-rings with a metal gasket, I use 1mm copper wire for anything I o-ring and it is a little easier on the gasket as it squashes a little rather than cut into the gasket. You can fit the o-rings to the head rather than the block if you dont want to strip the engine. You'd only want .006" or so protrusion if you use the steel gasket. I normally leave it .015" out for a copper gasket with a .008" receiver groove cut in the head. You will need to retension it a few times which can be a pain, especially with HKS cams without the notches to get to the head bolts easily.

Nice and informative stuff - thank you - i have heard mention that HKS make the best multi metal gasket.?

So if i buy another new HKS gasket, whats your suggestion.I will then get the head oringed. Use three bond also do you think?

Dave,

It is possible that SCE, makers of Top Fuel and Funny Car (7000+ horsepower) head gaskets, may be able to make you what you need. SCE has developed a process to "O" ring the gasket... instead of your head/block! This process is called their ICS system.

I called SCE and asked them if they have ever built an RB26 gasket. I based my request on the fact that they DO have SR20 gaskets. They said they have never built an RB26 gasket. I explained to them your current sealing problems and they believe their product is the answer.

Ok, now for the "rub"(bad news), SCE would need a head, a block, and an undamaged head gasket at their facility in southern California to ever PROPERLY design you an RB26 gasket. There is a market for a GREAT RB26 gasket, but to properly make it they need to have the major components to properly map out cooling passages, as well as checking proper bore spacing to see if their ICS system can be utilized.

Here is SCE's contact information, please keep us informed as to if you choose to pursue this, we have numerous clients from all over the world who might find this to be a desirable product!

SCE Gaskets Incorporated

4515 Runway Drive

Lancaster, CA 93536

Email:

[email protected]

Phone Numbers:

661-728-9200

1-800-GASKET-0

1-888-GASKET-1

Fax:

661-728-9202

We await further word from you. Thank you for your inquiry. I hope our answer is helpful! Please write back if you have other questions on these or any other products. When you're ready to order just visit The CyberAuto Family of Automotive Performance Web sites for your performance needs.

http://www.racing-seats-usa.com

http://www.alamomotorsports.com

http://www.fuel-pumps.net

http://www.fasthyundai.com

580 atw isn't all that much for a mls h/g to fail.

Head over to ct.com and the supra forums to see what those blokes are running. + Get the block and head finish correct; you will find your problems will dissapear.

^^^^ yeah i agree..... i would be looking at other issue's which are leading to the failure ie clamping pressure, detonation etc... if other people producing a lot more power than 580rwhp dont have an issue (which they dont) you need to ask your self what you are doing wrong.

Greddy make grommet type (instaed of bead) headgaskets for this type of thing too which i have seen run on the spec lists of some very tough jap gtr's (like phenoix powers 980hp gk powered monster).

SCE of course are going to say thier products is best...... doesnt every manufacturer.

Edited by URAS
Nice and informative stuff - thank you - i have heard mention that HKS make the best multi metal gasket.?

So if i buy another new HKS gasket, whats your suggestion.I will then get the head oringed. Use three bond also do you think?

I wouldn't pay the extra for an HKS gasket over a Cometic one. Personally, I wouldn't o-ring it if it was mine, for all but extreme cylinder pressures it's not necessary. Dont use any extra sealers on the gaskets, they have a coating on them already and adding goop to them increases the chance of them failing. Leave everything dry and clean and bolt it together.

All the SCE gaskets I have seen are copper, In reality they are great for race cars and were really good for street cars until MLS gaskets were readily available. Copper is great for sealing compression if you use an o-ring but not great for water and oil. I think the SCE gaskets have a silicone bead around the water holes but i would still stick with MLS. Copper has a tendency to continue squashing and needs to be retensioned every now and then. MLS gaskets only need to be done once.

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