L28 exhaust manifold source

[Virto]

Well, let's start with the good - the new master cylinder has solved my braking issues. And now let's get to the part that's even worse...

So the exhaust is shot, that was a known factor, and we knew the EGR tube was rotted out. What we didn't know until today is that the EGR port on the exhaust manifold was welded up by the PO, badly. We also didn't see that the manifold was cracked until we tried replacing the EGR tube.

Does anyone know which exhaust manifolds fit a bone stock Federal L28 - and then the next part of the question: does anyone have one in good nick lying around that they'd be willing to sell? Trying to get this back on the road is killing me with one thing after another and I'm starting to scrape the bottom of the cash barrel.

[Zed Head]

Your 78 has the N47 head with round exhaust ports so you can use any manifold from 1975 to 1978. Not a huge range. The earlier manifolds might work also, but they may also flow a lower volume, causing restriction. Not sure on those. The later ZX manifolds will bolt up but the head pipe flange is in a different location so your stock pipe won't fit anymore.

If you find one, make sure that the divider, that separates the front three cylinders from the back three, is intact inside. Also, have the mating surface checked for flatness and corrosion, they tend to twist and bend a little over time, plus exhaust leaks corrode the surface. Any good machine shop can grind it flat.although some charge more than others.

[EuroDat]

If your looking for one at slavage yards. You should look for a N47 (aug 76 to Jun78). The number is cast into the manifold. The N43 (pre jun 76) has the square ports and would bolt up to the N47 head. The P71 manifold is for the 280ZX.

Goodluck

Chas

Edited September 3, 2013 by EuroDat

[siteunseen]

You might get a mirror and look under your intake where the EGR tube couples up. They had a recall on '77's and the PO of mine didn't get the work done and it rotted the bottom out, big old pain in my a$$. I took a Sawz-All and cut the EGR plate off but the hole was too big to weld up so I had to get another intake.

[Captain Obvious]

They had a recall on '77's and the PO of mine didn't get the work done and it rotted the bottom out

What did the recall do? Do you have any links to more info about it?

[siteunseen]

page 194 in "How to Restore Your Datsun Z-Car", Wick Humble. VIN# HLS30-350001 through 410516 and GHLS30-060001 through 102141. If you don't have the book I'll scan it for you later, I'm at lunch now. The exhaust fitting came loose and the fix was a clip, part # 14741-H8216. Mine is HLS30-355834.

[Virto]

Sure enough, there's the recall info right on 194. I can't believe that they thought a spring clip was going to make everything OK - but I guess back then getting a replacement manifold wasn't much of an issue, either.

Thanks for the help and insight fellas. I've got a couple of feelers out now, and I can find intake manifolds left and right, but exhaust seems harder to come by. I'm kind of leaning towards MSA 3-2 headers with a smog fitting (gotta pass a sniffer) if I can't find a manifold.

[siteunseen]

I got the 6 to 1 and their 2.5" Premium Exhaust. Couldn't have bought anything better in my opinion, the look and sound is amazing as is the price, $1,000 or there about.

And I'm sorry to say but I threw away the cast iron OE manifold, would have gladly given it to you.

Edited September 3, 2013 by siteunseen

[Virto]

I like the 6-1 look, but I'd be killing my wallet just to spend the 500+ for the 3-2, the 2.5 premium exhaust and the new mounting hardware, not to mention the 50 or so to ship all of it.

The 3-2 is available with a smog fitting to run the EGR tube. MSA doesn't state if it'll fit the stock tube (that I just bought) or if one will need to be fabricated. If something needs to be mocked up, I could turn around and return or sell the EGR tube and at least get that 70 bucks back.

If I go the header route, I already decided just to buy the matching exhaust, since it's all bolt-on. It's not any more expensive than having a custom one bent up after the fact, and the little shop the car is at could do it at the same time.

The two big things that are keeping me from ordering the parts today are 1) money, including how much I'll pay for labor, and 2) Illinois smog laws. See - Illinois only exempts cars from 1948 or before, or cars with antique plates...which means I couldn't drive it on the street. There was a law that exempted a large number of 95 or earlier non-OBDII cars if they had a valid smog test at the time the law passed. The problem is that I can't verify if the car did, which might open me up to getting a sniffer notice in the mail.

[Virto]

Well, I think I'm leaning towards the 3-2 and matching exhaust. I talked to the shop owner today and he thinks it's probably the better way to go, since they'll connect to the factory EGR and there's no real way of knowing just how well another 35+ year old manifold will hold up.

If ever I wish free shipping was an option, this will be the case, . Amazon spoils me. I see a number of folks with 6-1, anyone have anything to say about the 3-2?

[Jeff G 78]

I likely have an OE manifold, but I'd have to check to make sure the studs are there and the port is intact. I just threw one away a week ago, but the studs were broken on that one. I have two more spare N47 engines that have manifolds on them. Let me know if you want me to check. I will be bringing them back from storage this weekend.

[Virto]

The exhaust on the car is rotted out in place beyond the manifold, so it all needs to go. Originally we were just going to patch the holes and replace the EGR tube and then worry about the rest of the system next year, but if the intake and exhaust have to come off, it's probably best to do it all at once - and having something custom bent wouldn't be any less expensive than the MSA exhaust.

I'm going to try ordering the header and matching exhaust - if, for some reason things go poorly, I will probably take you up on your offer. Seems a lot of people have tossed OE manifolds recently, they're surprisingly hard to find, unlike the intakes. Thanks though, Jeff.