I'm hoping someone who's replaced the exhaust/intake manifold gasket on their 240z can give me an answer to this question; I have a new Nissan OEM Gasket- one side has flat metal plating that extends outside the perimeter of the holes; the other side doesn't. Does anyone know which side is supposed to go against the head?

In other words, does the side shown in this picture go against the head?

Edited July 24, 201311 yr by lm71z

I installed mine with the metal out, facing the manifold.

I installed mine with the metal out, facing the manifold.

Okay, thanks for the quick reply. I have a few more questions for everyone.

1. Are there supposed to be lock/spring washers used when attaching the exhaust manifold?

2. I'm replacing the gasket because it was leaking, primarily from the middle two exhaust holes. I just removed it and noticed that the rear 3 exhaust holes in the head are clean, and parts of the holes are a white color. The front 3 exhaust holes in the head are fairly greasy and completely black. Is this an issue of the front carburetor running too rich and/or the rear carburetor running too lean?

Edited July 24, 201311 yr by lm71z

It is normal to have some black soot build up on the exhaust runners but if it looks wet/greasy as you describe that might indicate leaky valve seals.

1. Are there supposed to be lock/spring washers used when attaching the exhaust manifold?

I had that same question when I did mine. The stud kit that came with my header had normal hex nuts without any locking washers. I felt that they would back off so I went to my local Nissan dealer and got what he called "conical nuts" or just slightly out of round. If they spin on really easy I wouldn't use them, the out of round will not finger tighten easily you have to wrench them down, that's what keeps them from backing off. I went bigger also, some of the holes were wallowed out pretty bad on the head.