Grind off material

[DuckManNK]

Probably a dumb question: Does this material need to be ground down?
The header was mounted like this for who knows how long.
Any header I have seen has a flat mounting surface.

[siteunseen]

I don't see any leaking, black soot, so maybe the intake gasket sealed it up good enough. I would measure the protruding section of the header. It may fit inside the exhaust ports?

My 2 from MSA were flat as you say. Is there a name anywhere readable like Pacesetter? Those are cheap headers but like I saw there doesn't look like any leaking.

Was it noisy? Ticking like a bad exhaust manifold/header seal. 

More info on any type problem or noise would be helpful to us.

[mailnome]

The area around the ports that looks like it is raised 1-2mm?

I would think it would be fine, but maybe there’s an argument that the header has more of a chance to warp. It should give good pressure against the gasket surface around the ports though.


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[Zed Head]

I think those are intentional.  They raise the pressure, force per unit area, on the gasket to give a better seal.  

[grannyknot]

It's easier to get those raised areas flat than the entire flange and as said above the concentrate the pressure.

[DuckManNK]

Thanks for the info.
This is after I cleaned them up.
Cylinder 3 was ticking, and the exhaust part of the gasket was blown out right next to it.
New gasket is already installed. I still need to change out the valve stem seals.

[Racer X]

15 hours ago, DuckManNK said:

Probably a dumb question: Does this material need to be ground down?
The header was mounted like this for who knows how long.
Any header I have seen has a flat mounting surface.

The raised area is the weld between the flange and the tube. It gets machined flat and true when Newton aid in sealing when the intake and exhaust are installed.

A quick cleanup with a large flat file is a good idea before reassembly. Careful to not cut them out of true or damage them.

 

[DuckManNK]

Just wanted to share what the gasket looked like.

[Racer X]

14 hours ago, DuckManNK said:

Just wanted to share what the gasket looked like.

That gasket isn’t correct for use with a header. It looks like an OEM gasket with a sandwich of metal and fiber. The header gasket is all fiber, with no metal embedded in it.

[Zed Head]

You'll want to check the flatness and quality of the surface on the head.  Maybe have both surfaces skimmed.

There's another Datsun site out there with a couple of guys that say they don't use any gasket at all.  They just mill both surfaces and bolt it up.  They say it works but who knows.

Anyway, the head surface is often overlooked.

[grannyknot]

5 hours ago, Racer X said:

That gasket isn’t correct for use with a header. It looks like an OEM gasket with a sandwich of metal and fiber. The header gasket is all fiber, with no metal embedded in it.

I've never heard that before, what is the rational behind having no metal in the gasket?

[siteunseen]

Mine's got a lot! Not in it but outside of it.