Header

[Toonsis]

I have a 73 240z. I am looking for a header to replace older rusty warped header. I ordered a Pacesetter from Black Dragon(Victoria British). When I placed the order they asked me whether I needed square port or round port. I advised them that I needed square port. When I received the header, it has ports 1,2,5,6 as round ports and 3,4 as square ports. I called back to Black Dragon and asked them about the difference and they told me that is what they had. I had them look at the catalog that clearly shows the gasket with all square (the gasket ports are the same as the header they sent me) and they said that it must be a misprint. I then called Pacesetter directly and they told me that they are now making this header this way so it will be universal between the square ports and the round ports heads. I explained that putting on this round port header would cover some of the square exhaust ports and they told me that it would not matter. Really??? Pacesetter also told me that they have 240z race teams that buy these headers and swear by them. Pacesetter's part number is 70-1037. I would think that first of all it would blow out the gasket if the gasket is round and not as big as the square port and I dont want to restrick the airflow coming out of the exhaust. Has anybody else heard of this. I need to find a header or manifold that is not warped for my car. I don't have alot of $ to spend and need to get my car back on the road. Please help.

[Toonsis]

I have read some of the other posts and I would like to go back to a stock manifold. I also have read that there was a problem with manifold warping in the middle.. How true is that and where would be a place to look for a manifold? I have looked at e-bay and have not found one. I would perfer one with no smog hookups so I would not have to plug any holes. I do have the original downpipe to bolt on to the manifold if I can find one.

[tlorber]

Well, I've got both a square port header, and a stock manifold from a '73 but I'm out in California. Not sure how much shipping would be. I just replaced my stock manifold (which DOES have the smog injectors etc.) with an MSA 6 into one. Other than having to grind the thick washers to compensate for the intake mani/header thickness difference I'm pretty happy with the fit and performance.

[Z train]

Toonis-you're on the right track with the manifold idea.

[Arne]

In the USA, all 240Z stock manifolds have smog fittings. Not sure about the square-port 260/280Z manifolds. The downpipe you have for a '73 may not fit other year manifolds, especially the '75 and up.

[Galaxybj]

Here's one in NY on ebay - http://cgi.ebay.com/ebaymotors/USED-Datsun-240Z-260Z-280Z-Exhaust-Manifold-_W0QQcmdZViewItemQQhashZitem2eb0667b68QQitemZ200528001896QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

[Carl Beck]

Where in Florida are you located?

[Toonsis]

Carl, I am located in Ocala Florida. Thank you for all of the replies everybody. They have been helpful. If I find a stock manifold, is it wise to try to remove the smog hookups and replace them with plugs to dress up the manifold?

Edited October 8, 2010 by Toonsis

[Inf]

FWIW when I pulled all my smog gear 6 or so years ago, I also took all the air injection ports out of the exhaust manifold. I ended up destroying a lot of the rusted male threads holding the injection ports in, so there was pretty much no turning back. I plugged the holes with some brass fittings, but IIRC, I had a pretty hard time finding something that would fit...