[Tom Vaught]

Because the ring (Marty's) is being pushed equally from all sides and also upward by cylinder pressure, the ring typically tends to stay located in one spot. Now there will always be vibration in the block but the rings should not "Fret" which is a fancy engineering name for the 'Itching' you are asking about.

Tom V.

[Chris Uratchko]

Yes thanks I'm aware of Fretting.

Anyways I'm not concerned about the rings. I'm concerned about the aluminum head mated to the iron block. Just as a main cap will 'fret', or any 2 metal to metal surfaces mated in the engine,.... I can see a tendency to have the head and block do the same thing.

Unless I am mis-understanding that there will be something between the head and block surfaces?

[73 TRANSAM]

I had to remove my heads for more mods and I have this rings installed in my setup. The rings cut thru the heads surface and now I understand why it seals better. I haven't completed my project yet so I cannot share anything yet.

[455firebird1969]

The potential for fretting is there when using an MLS gasket, or a metal O-ring between a head and a block. The dissimilar metals in both cases will eventually lead to a form of deterioration (fretting corrosion) if they remain in contact without a barrier. Whether or not it is referred to as corrosion or fretting, it is still not going to be happy when left in contact for a long period of time. On a race engine the timeframe the parts are together is minimized. When added to the shortened lifespan of racing engines the risk caused by dissimilar metals will be offset by the ability to seal the head. It sounds like a good compromise when gaskets cannot hold the pressure.

[Tom Vaught]

When using the solid rings, the rings are basically like 4.0"+ hollow "house piers" that are the only things holding the heads away from the block. So the normal surface of the block will never touch the heads surface, (cast iron to aluminum). Only the rings will touch the two dissimilar metals surfaces.

If the studs are properly selected and torqued for the rings and the head/block, the heads will not be able to move upward away from the rings and the block.

If there is some thermal growth, the heads being held securely by the studs/washers will try to expand in all directions (as will the block and rings) and still try to be clamped together.

Only the pressure in the cylinder (15%/25%) higher than NA combustion pressures will be trying to push the two parts away from each other. It will also be trying to make the sealing ring bigger in diameter and if designed correctly will lock the ring tighter into the head surface.

Tom V.

[[email protected]]

I understand how the rings seal the chamber but what about the valley pan area with oil draining back. What happens there?
Kevin

[73 TRANSAM]

It needs to be sealed with silicone as the oil blow by and oil will be all over the engine. I put a bead around the head to seal it.

[Chris Uratchko]

Originally Posted by Tom Vaught

If the studs are properly selected and torqued for the rings and the head/block, the heads will not be able to move upward away from the rings and the block.

.

That's not accurate. The fastener is not the issue. The column of aluminum under the fastener is the weak link.

If you ever have a chance to do a pressure map on a deck(which everyone building engines should do) you might be surprised at how much a cylinder head bends when you torque the fasteners. And where clamp loads on the gasket surfaces actually occur. More load on the fastener does not equal more clamping force in most instances. Most castings I have tested are not able to withstand the torque that people try to apply with larger studs and higher loads. Instead the head deforms and bends and you have isolated clamping right under the fastener column, and nearly zero clamping force anywhere else..... due to the column compressing and not distributing load across the deck....

In other words, these types of scenarios are what are driving things like sealing rings.... improperly designed castings, and improper assembly methods.

[J.C.you]

perhaps one could copper coat the voids between the surfaces and machine the aluminum head for a cast iron insert (receiver surface) for the rings.

[Elarson]

Originally Posted by Chris Uratchko

That's not accurate. The fastener is not the issue. The column of aluminum under the fastener is the weak link.

If you ever have a chance to do a pressure map on a deck(which everyone building engines should do) you might be surprised at how much a cylinder head bends when you torque the fasteners. And where clamp loads on the gasket surfaces actually occur. More load on the fastener does not equal more clamping force in most instances. Most castings I have tested are not able to withstand the torque that people try to apply with larger studs and higher loads. Instead the head deforms and bends and you have isolated clamping right under the fastener column, and nearly zero clamping force anywhere else..... due to the column compressing and not distributing load across the deck....

In other words, these types of scenarios are what are driving things like sealing rings.... improperly designed castings, and improper assembly methods.

Exactly right! Everyone needs to absorb that. I'd also add that the "bridge strength" of the head between studs is a big deal too. Our billet funny car heads seal terrific across the whole gasket. No water jackets, approx 1" taller than a stock head and a minimum .25" wall around all studs makes it way stiffer than typical.

Eric

[Robert C.]

Look at this link. We have used this to better our products.


Fujifilm Prescale® Tactile Pressure Indicating


http://www.sensorprod.com/fuji-prescale.php

It will show you things you want to know and give you a big surprise.

[Glenn Sedig]

Originally Posted by cgeise

what about the rings working on the aluminum head causing the head develop wear marks ?? Similar to the old head gaskets with steel o ring in them.

When running alum heads with kimetic gaskets the web in the head between the center two cylinders gets hot enough to anneal the alum and then the ribs in the head gasket presses grooves in the web. When running your new rings how deep can the grooves be before it will not seal? Or do the rings disperse the heat away from the web fast enough that the alum is not annealed?

[Tom Vaught]

Originally Posted by Chris Uratchko

That's not accurate. The fastener is not the issue. The column of aluminum under the fastener is the weak link.

If you ever have a chance to do a pressure map on a deck(which everyone building engines should do) you might be surprised at how much a cylinder head bends when you torque the fasteners. And where clamp loads on the gasket surfaces actually occur. More load on the fastener does not equal more clamping force in most instances. Most castings I have tested are not able to withstand the torque that people try to apply with larger studs and higher loads. Instead the head deforms and bends and you have isolated clamping right under the fastener column, and nearly zero clamping force anywhere else..... due to the column compressing and not distributing load across the deck....

In other words, these types of scenarios are what are driving things like sealing rings.... improperly designed castings, and improper assembly methods.

The post was accurate, The Palbykin/Earhart rings were originally designed to seal up a cast iron head. There was a reason why that head was chosen and worked well for several years with the ring. The best performance of the little 406 cid pontiac engine was with the cast iron head vs the later tried Aluminum head.

So the head being a poor design, (column strength wise) is not a ring problem. It is a head design problem as you said. I stand by my post and the info posted.

A Custom Head like Mike and Eric run will seal fine and a head with column strength issues will have head gasket issues. A Pontiac Guy cut away a bunch of the head bolt columns material during a porting job and had sealing issues on a NA application, forget about a Boosted engine. Blamed it on the head, the issue was he took away what little strength that the head was designed with.

Food for thought. You only have so much room to put stuff inside a given bore spacing head. When you increase the bore spacing you can make the dimensions larger on the internal column parts. A solid head is another choice.

There was a reason why the Chebby boys went to the larger bore spacing dimension in the early 60s. The Pontiac guys will have to design band-aids to fix these issues if the bore spacing (no wiggle room) does not change OR AS ERIC HAS SAID, CAST UP A GOOD CAST IRON HIGH FLOW HEAD.

Tom V.

[Tom Vaught]

The ring will work with aluminum heads but we are seeing much more often the head bolts collapsing the material around the fastener. Heat, marginal cooling, high boost, larger fasteners that collapse the head columns even quicker.

If the exhaust side of the head resembles the RA-IV configuration at some point you may have issues. The RA-V design has different thermal conditions.

Tom V.

[Tom Vaught]

Thanks for the info from years ago.

Tom V.