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Hi guys. I was wondering if anyone have experienced failure with cometic head gaskets i have used them for years and sad to say every head i pull off thats been placed under high amounts of boost. Seems to fail at the main sealing ring. Like what the hell im now catching on to this. I think it has to do with a shape edge to clean of a cut i guess. The older composite gaskets never show these kinds of failure. I did a 2jz motor some time back and it had an apexi gasket i notice it was MLS gasket but on the inside of the main sealing ring it had like a edge that wrapped around the shape cuts of the MLS gaskets. Like the old composite types. Think it has to do with hot spots like heating up a sharp knife and the thin parts gets red first and fails. Or is this just a crapy / brand gasket. What do you guys use. Thanks in advance.

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I had one on my sr20 with ARP 2000 studs. Lasted about 5 years and then started leaking combustion gasses into the water jackets in several places when on track. Wouldn't use again although 5 years service was reasonable I suppose.

Cometic have not such a good name when used on a few different makes of engines.

I know they are prone to failure on S2000 engines, especially if adding boost to them, everyone was using either OEM (factory is a MLS Gasket) or any other aftermarket MLS brand.

There are thread after threads about Cometic failing on those engines, especially if using ARP bolts, the only ones that have not failed have had the rocker covers removed and retorqued every 5000Km......

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