Chris White

For those of you that liked the Cometic HP MLS gasket…..sorry, its no longer available….but that’s the good news!

About a year a go I looked into gas filled O-ring technology (as in F1 type head gaskets) but it turned out to be a little pricy – about $200 per O-ring, yep – times 4 for our engines. $800 to $1000 seemed a little pricy for a head gasket.

I was chatting with the techs at Cometic and they are about to release a new head gasket based on the Garlock Helicoflex gas filled O-rings. Neat stuff, I will have one hear by the end of the week for a 2.7 motor I have apart. I’ll give it a good torture test and see what happens.

The gas filled O-ring technology allows for some movement/expansion and it will still keep a seal. In fact the gas filled O-ring expands under heat.

This looks to me to be the first use of new technology in head gaskets for quite a while. Hopefully it will be the holy grail of head gaskets!!

Chris White

PS – about twice the cost of their HP series…

Duke

NICE!

David Floyd

Hope they make it for 106mm bore

Porsche-O-Phile

I'll take two.

Chris White

Thats my first order, a 106mm bore 2.5 style gasket! I'll see it first thing next week!

David Floyd

Whew !

Tom M'Guinn

I imagine it would not work with an o-ringed block, right?

Chris White

I will have to check. It may depend on exactly where the groove is.

toddk911

Copper head gasket?

Also, is it a good idea to have a super bad *** head gasket that doesn't go before the motor itself blows?

BC

How much room is there for a gas filled o-ring? Would this not warp the head without having a groove?

ehall

Hey Chris
Where can we get more info on this technology?

hosrom_951

Ditto

I would definately be in for stock 2.5 (100 mm), but when would it be available (for everyone) is the question.

ehall

I won't go that far. I really want to learn about how it works, what its made of etc. I'll wait for Chris to send an engine into orbit, or make it work, before I want one, but Chris' opinion and testing would go about as far as I would need, to tell me the real story.

Chris White

I will take some pic and post more info when I get one in my hands.
Technical info on the Garlock Helicoflex seals - http://www.helicoflex.com/assets/pdfs/oring.pdf
Sure sounds like what we want!

As for the ‘super bad ***’ concept – I have toasted my share of head gaskets over the years. I don’t really believe that it will come down to the head gasket goes or the rods fly out the side of the block. I want a head gasket that will hold up to the conditions in the engine design. We have all seen pictures of the #4 cylinder failures – this is not a safety fuse issue – the head gasket cant cope with the combination of very high heat / pressure and structural issue (as of yet to be defined) that casue 90% of all head gasket failures to happen in the same spot.

A couple of years ago I torture tested a MLS gasket on a one hour track session running at 9.5/10ths the whole time. I knew the inter cooler was heat soaked after 20 minutes but I kept my foot in it to see how it would hold up (it was the last event of the season – what the hell!). At about the one hour mark the metal core on the gasket melted. It looked like it got soft and was pushed out of place by the pressure – exactly where the usual failure point is. My point is that the concept of the head gasket as a fuse is incorrect. If you go into heavy detonation your head gasket is not going to ‘save’ you. If you mixture is incorrect your head gasket wont ‘save’ you.

I hope that this new design will work…won’t know until I torture it some!

Currently the O-rings are only available in 105.15 and 106.7 mm diameters. These can be used in head gaskets with significantly small openings. I think that you can use these down to 102mm easily and possibly stretch them further. I will have to look at the design to draw a final conclusion.

Chris White

BC

SO this new gasket would require a ring groove (from reading the link you posted)