Missing Stock Exhaust Manifold for 68 2000

[DCroadster]

Are the stock manifolds cast iron or steel? Question being are the stock manifolds fixable if there is a leak, ie can they be welded if there is a visible crack?

Rob

[JT68]

They are fab'd from several pieces of stamped steel, so yes they can be welded. The issue becomes, however, that after you weld it up, a few months later a hole opens up close to the weld or somewhere else, because half the metal has rusted away on the inside. The collector and the center Y are the worst spots. If you really,really want to repair one, suggest you get it commercially (as in big compressor/high pressure) sandblasted first. That will blow a hole in most unknown thin spots and show you what you really have to work with. Often a header is the more practical choice unless you are lucky enough to find a replacement Nissan manifold that is only 25 years old or so.

If it is a 50 year old "original to the car" manifold, you might have a 50/50 or worse shot at a successful repair.

[Gregs672000]

As JT68 said, any welding has to be done right. I had mine welded up more than once before finally throwing it down the alley in a "I'm done with this crap!" demonstration many moons ago. IMHO, switching over to a header, while a little more involved with the changes necessary to the exhaust collector (good time to do a flex pipe) at a muffler shop, a header is a much better, more permanent solution. It also depends upon what kind of shape your exhaust is in now... for example, the condition of the stock exhaust pipe mounts, etc.

[DCroadster]

Thanks JT and Greg,

I have been looking for a long time and just bought mine off chance this 3/11, which happens to be an important date in this community, in pieces. Rust free, but numbers matching. I like putting together cars as stock, but as I look further into the availability/cost/repair of parts, it may be best to go with a header as suggested.
Right now, the header that came with is totally rusted away and the exhaust system is non-existent, so I can do what I want, but would like to route it similar to stock, I see a few options.
I saw an original rusted manifold with confirmed hole on eBay and a header for sale in my area, so I went with the header as I asked this question on the forum. I am happy with my choice as you have confirmed that going with the manifold would have led me down Greg's path, loads of frustration.
I am really enjoying the wealth of knowledge and openness in the Roadster community as I have started to work with the vendors, such as JT, and read in the Forum.
I will be scouring for parts in the Eastern part of the country as well as by electronic means, so I will be meeting a lot of you.
TIA,
Rob

[Gregs672000]

Hey, that's great to hear Rob! This really is a great community of owners and a fun car to own. There's just something about this car that brings out a smile on your face, and on other people's faces when you go driving it. The family here truly enjoy helping other owners, being helped, hearing about adventures, talking modifications... you name it. And there's no worry about asking questions or getting lost... we'll help!

[Gregs672000]

Speaking of super quality and "stock" (actually much better I hear) looking/functioning exhausts, pretty sure JT can hook you up!