Need to make exhaust manifold gasket, extremely high heat

foxtrapper wrote:

Swank Force One wrote:

Spoolpigeon wrote:

Bobzilla tells me that's only rated to 800F. That's not gonna cut it.

Really? Damn. All those warped headers and such that I've successfully sealed with it over the years. Guess I'll have to tell them they aren't working. Seriously, the stuff works quite well, though it won't hold up a gap where the exhaust gasses are directly burning it.

This is what's between the wrapped header and downpipe on my new engine.

GameboyRMH wrote:

foxtrapper wrote:

Swank Force One wrote:

Spoolpigeon wrote:

Bobzilla tells me that's only rated to 800F. That's not gonna cut it.

Really? Damn. All those warped headers and such that I've successfully sealed with it over the years. Guess I'll have to tell them they aren't working. Seriously, the stuff works quite well, though it won't hold up a gap where the exhaust gasses are directly burning it.

This is what's between the wrapped header and downpipe on my new engine.

Does your new engine turn a 20 pound mass of cast iron glowing orange?

Look at that glow, it's probably not up against the head, but down closer to the collector. Thermal mass and a water jacket keep the head cooler, and the parts bolted up to it cooler.

Though perhaps it is simply a no-go.

Notice the steel ring inside the hole on this one?

That and flat flanges are all you need. I've gotten them by digging through the flange gaskets at the local parts house, or there are universals available: http://www.jscspeed.com/catalog/Universal_Exhaust_Gaskets-150-1.html

Swank Force One wrote: I think i worded this wrong. I need to make the gasket that goes between the head and the manifold. There won't be anything pre-made available. Any idea what sort of material your stuff is made from?

I use black Right Stuff.

I used to use the 700 degree rated orange/gold silicone, but Right Stuff seems to work just as well.

I started doing this when I got fed up with burning out Mazda gaskets and was willing to try anything. I love the sound of rotaries but one with a header leak sounds nasty.

Swank Force One wrote:

Spoolpigeon wrote:

Bobzilla tells me that's only rated to 800F. That's not gonna cut it.

How hot does the aluminum in the cylinder head get? Think it's really getting up to 800 degrees? I don't, and the silicone won't either. It'll be fine, says the voice of experience.