Porsche-O-Phile

Excellent pics. Is the ridge part on the top of the cylinder wall made of metal or some sort of composite or what - looks reddish. In other words, what's the actual O-ring made of?

APKhaos

Most head junction o-rings are copper wire.

Ski

O-rings are copper and the joints - they are toward the exhaust head stud for that cylinder. I am taking my time building a spare engine: block is done, pistons are coated, bearings are teflon coated, rods are at EBS have the oil shed coating applied.

theedge

What is the logic behind aiming the joint a certain way?

Jon Schepps

I don't know if its still true, but when I spoke with the engineer at Cometic (who makes the MLS gasket that's sold by several vendors under their own names) they had two versions, one for use with o-ringed head or block, and for non-o-ringed use. The difference is a slight thickening of one of the metal layers around the cylinder wall that kind of acts like an o-ring for non-o-ringed engines.
When I bought from Cometic, they asked which one I wanted. They will also make them to any thickness and bore diameter you want.

I'll second the statement that this gasket is best used when both the head and block have been freshly surfaced. It is not a cure for a poor seal (AMHIK). It has no real advantage over stock or WFR gaskets for stock applications.

Pelican Products has a good price on the WFR gasket.

Jon.

OriginalSterm

cometic also has a headgasket designed for turbocharged (or supercharged, or nitrous injection) and NA motors. make sure you specify which version you want.

Evan70

The MLS looks exactly like the gaskets Tom Charlesworth uses and recommends. He says the ones he uses were a custom design by one of his suppliers that nobody else sells, but who knows how accurate that is. Anyway, he runs them on all his personal 951s, and recommends them to all his customers that need a new headgasket. So Charlesworth, and probably many of his customers, are running MLS gaskets. Now whether his customers know they are an MLS gasket or not is another question...

Ski

Yes they know Evan, but there have a been a couple of those gaskets cut "as needed" for special builds - custom diameters and thickness, especially for the 2.8 stroker and the 3.0L turbo that's being built at the moment. Tom had the 104.5 turbo pistons the other day at Hallett before they went to the coater. Myself and Jim were the first to show him the Cometic.