copper head gasket, and \"O\" ringing

[89325iturbo]

I've used a copper head gasket in the past with just a copper gasket sealer, but it never worked. for my new turbo set-up i bought a copper head gasket again, but wanted to do o-ringing this time around. First can i o-ring both the head, and the block? i read about most people doing one or the other mostly the block. I don't see why you couldn't o-ring both. Unless its because of having a cast iron block, and aluminum head since they expand, and contract differenly you might not want the gasket tied in to both the bottom and top end. I could see how you might want a little flex between the two. Any one here running a copper head gasket with high psi levels? Or anyone have any insight into o-ringing? Last what are you guys using for head gaskets for high psi if not a copper one? thanks

[Turbo_Bimmer]

When I bought my copper head gasket from Flatout group, they specified that above 2hp per cid, o-ringing was nescessary. Above 3hp per cid, o-rings + receiver grooves were necessary. That means that you o-ring the head, and with precise alignment, you make a groove into the deck of the block. I suppose having a groove in the block let the gasket deform a bit and entering into the groove, making a stronger seal.
Flatout group make what they call a RCC gasket, which is: Rubber Coated Copper gasket. It's supposed to seal better than any add on sealer like Hymolar and such. It is a very thin (0.002") layer of translucide rubber melted to the gasket.
Their site show many top end drag racers using their gaskets, so that convinced me to try one.

Michel.

[bilodeaulynn]

SCE gaskets recommends "o" ring for any copper head gasket. I have one on my 745i. Had stainless "O" ring put in the block (after a light resurface of the deck surface to insure it was perfectly flat). Then torque on the head without a gasket to make an imprint with the "O" rings that are protruding slightly out of the deck surface of the block. They then machine a matching receiver groove around each combustion chamber. The receiver groove should be a little bigger than the "O" ring. this allows the gasket to be pushed up into the groove when the head is torqued down. Head was also surfaced taking off the minumun necessary to make it perfectly true.

I suppose you could place the ring in the head and the reciever groove in the block. I used Yamabond around the water and oil passages. No leaks so far, although everyone tells me I will develope a trickle sooner or later.

Lynn

[89325iturbo]

So you O-ringed the block, and head.

[bilodeaulynn]

Technically, only the block is "O" ringed. The head gets a receiver groove, but no "O" ring. I posted some pics in the gallery. Click on e23 and search for ""O" ring procedure". I did not know how to post a pic here and didn't feel like learning tonight. I am sure it isn't that hard, just didn't know what to do.

Lynn

[///ARINUTS...]

[Turbo_Bimmer]

You cannot use o-ring with a stock gasket. O-rings are used with copper gaskets, and with the clamping force of the head, the o-ring forces its way into the gasket. If you have receiver grooves, my idea is that the pressure made by the o-ring, will push the copper, a little bit, into the groove for a better seal.
On my engine, I have only o-rings since my application will be around 2.6 to 2.7 hp per cid.
The use of high quality studs or bolts is a big plus.

[89325iturbo]

i understand what your saying now, i was unsure if the cylinder head got an 0-ring or not, but its just the reciever groove. Did you have yours done at a shop? I have zero clue how much oringing would cost. I'll have to see if my mashinist can do it, im unsure if he has the machine to cut the grooves, as its not a big place.

[///ARINUTS...]

My block is O-ringed, I'm using a stock gasket. I'm not aware of a reciever groove. Maybe the reciever grove is something you need for a copper head gasket.

[bilodeaulynn]

OK guys, here is the scoop.

Copper head gaskets. I suppose there are some brave souls out there that would try it with no "O" ring, but all manufacturers recommend "O" ring in either block or head and a receiver groove in the other. I have no doubt someone out there is running just a "O" ring in either block or head without a receiver goove, but it is not recommended. I made my decision after talking to a racer friend of mine whol uses aluminum heads on a small block chevy (runs high eights in the 1/4 mile in a steel bodied Firebird with full interior, with no nitrous, no boost and just 316 cubic inches, so he knows what he is doing). Does that mean there is no other way? Not at all.

Now as far as "stock" head gaskets, I think most people are referring to a composition gasket. Yes, you can use an "O" ring set up. In fact before I built this set up my 745i, I had "O" rings in the head only, and no receiver groove in the block, using a composition head gasket. I ran 15 psi of boost and never had a failure. Any machine shop that can do an "O" ring job for you will insist on having the head gasket in hand. On a composition gasket, the idea is to locate the ring just to the outside of the inside diameter of the compression bead. The "O" ring is NOT intended to make the seal. It is intended to prevent the compression bead from getting pushed out.

Unless you are running more than 15 psi of boost (I had about 8;1 compression in that motor, a little less than stock) I think the best bet is the compostion gasket. I little more trouble to keep water and oil sealed with the solid copper, although I must admit I haven't tried the one with the thin coat of rubber. May be the best of both worlds, I just have eno experience with it.

As far as cost, I really don't remember exactly. I do know I spent a little less that $400 altogether at the machine shop. But I had both block and head cleaned, skim cut for a perfect mating surface, pressure tested for cracks etc. My best guess (without pulling the invoice) is that about 230 to 250 of that was attributable to the "O" ring, receiver groove operation.


Hope this helps.

Lynn

[///ARINUTS...]

I am using a stock composition gasket. the block is "o"-ringed. the head has no receiver groove. at the moment the head is off the block. So Now is a good time to have this grooved made.

Or am I off the ball once again and should not have this done because I use a stock composition gasket???

I'm getting confused.....

[Turbo_Bimmer]

It depends of the stock gasket. If you use o-rings with a stock gasket, you don't only have to make sure that the diameter and centering of the o-ring aligns precisely with the firering of the stock gasket, but also, the stock gasket needs to have that firering perfectly roung. (Having o-ring aligned with the composite material won't do the same, opposed as having the o-ring directly on the firering, at least it's what I think).
On my engine (M42) there are valve pockets designed in my stock gasket. So the shape of the firering is round, plus 4 notches where the 4 valves are to clear them. Using o-ring with a gasket like that wouldn't seal where the pockets are. Big chances are that most of the 4 valves per cylinder BMW engines are build like this.

>If I can find the reason why my images don't show up in my posts, I could post a picture of my stock gasket to make it more visual<

[bilodeaulynn]

You do not need or want a receiver groove with the composition head gasket.

Lynn

[///ARINUTS...]

have very different head gasket design than you M42 gasket. I have a round fire-ring with no notches.

So I am unsure If my "0"-ring is good or bad now because I don't have a reciever groove.

I don't want to use a copper gasket yet anyway, I am running sub 10psi boost levels

[///ARINUTS...]