Anybody ever used a Copper Head Gasket

[FiatMac]

After getting part way through my performance engine build, I have concerns that the quench gap is too large. The performance head gasket I have (Ajusa) measures 0.058" thick. If I assume 0.008" compression of the gasket, then the compressed height is 0.050". The block was decked lightly to get a good surface, and the deck height is 0.018". Therefore, my quench gap is 0.068". From my research, it appears that it is pretty much universally agreed that the quench gap should be in the range of 0.035" to 0.045" to improve resistance to spark knock. So, I am almost double that gap.

I have been looking at the use of a copper head gasket to get the quench gap down into the recommended range. Below are links to two web sites for manufacturers. Both make custom gaskets. The first site (Gasket Works) lists Fiat 2000 in their archive of gaskets. I have sent email to both but have only received a reply from Hussey saying that they could make one if I sent them a gasket for a pattern.

http://www.headgasket.com/gaskets.html
http://www.husseycopper.com/HusseyGaske ... askets.htm

The web sites indicate that these gaskets are used regularly in racing applications. My concerns are around sealing of the oil and coolant passages. Anybody out there had any experience with this type of gasket?

[azruss]

So you are talked about taking 20 to 30 thou of a 60 thou gasket. that give you a gasket that is 30 to 40 thou thick. that is still a pretty substantial piece of metal. (thickness of 10 sticky notes) Had a chance to hang in the pits of a AA fuel dragster. they tore the motor down between every run. They used the same copper head gasket over and over again. just cleaned it with brake cleaner and smeared RTV on any scratches. It didnt look like they were using gaskets any thicker than you are talking about. On the other hand, their gasket only had to hold for a minute or so.

[vandor]

I have heard of two people who tried a copper gasket on a Fiat TC, and both leaked badly.
I do not know if they make a gasket that thin, but I've used Cometic multi-layer metal headgaskets with success.
Call them, see if they can help you.

FWIW, when I was in the same situation, I just decked the block 0.050" (1.25mm). I am sure you realize this will increase you compression ratio? Without doing the math I'd guess that a gasket that is 0.030" thinner will increase CR by about half a point.

[TX82FIAT]

FiatMac, I will be real interested to know about the sealing around the oil and collant passages. I have an almost identical gap issue creating a very small oil leak currently. Before tearing into the car a thi8cker copper head gasket has crossed my mind. Let me know how this works out.

[FiatMac]

but I've used Cometic multi-layer metal headgaskets with success.
Call them, see if they can help you.

FWIW, when I was in the same situation, I just decked the block 0.050" (1.25mm). I am sure you realize this will increase you compression ratio? Without doing the math I'd guess that a gasket that is 0.030" thinner will increase CR by about half a point.

Csaba,

The engine block is already completely assembled so I would have to completely disassemble to get the block decked. I am looking for an alternate solution. Yes, the compression ratio would go up if I stick with a standard combustion chamber on the head. The head has not been completed yet, so I could compensate by increasing the combustion chamber volume slightly.

A multi-layer would be better. Does Cometic have a multi-layer gasket for the Fiat TC?

[Curly]

I've tried copper head gaskets on a couple of BMC competion cars (Austin Healey Sprite & Cooper S) both weeped coolant constantly from the gasket joint despite the application of sealant to the gasket. Have now gone back to the regular gasket types and have no issues.

[131]

A multi-layer would be better. Does Cometic have a multi-layer gasket for the Fiat TC?

They do, in varying thicknesses, but they're hard to track down.

[vandor]

A multi-layer would be better. Does Cometic have a multi-layer gasket for the Fiat TC?

They do, in varying thicknesses, but they're hard to track down.

I've had no problem with their customer service, FWIW.

[131]

They do, in varying thicknesses, but they're hard to track down.

I've had no problem with their customer service, FWIW.

I mean finding part numbers on the web, I've never dealt with them directly. I've found numbers for 16v and reverse port 8v, but not for our earlier engines. I know people use them so they obviously exist.

[FiatMac]

I've tried copper head gaskets on a couple of BMC competion cars (Austin Healey Sprite & Cooper S) both weeped coolant constantly from the gasket joint despite the application of sealant to the gasket. Have now gone back to the regular gasket types and have no issues.

Thanks for the info, Curly. Sounds like something I should stay away from.

[FiatMac]

A multi-layer would be better. Does Cometic have a multi-layer gasket for the Fiat TC?

131 wrote -"They do, in varying thicknesses, but they're hard to track down."

Vandor wrote -"I've had no problem with their customer service, FWIW."

Thanks Csaba and Mick! I have sent a query by email to Cometic. Will follow up with a phone call.

[fiatfactory]

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