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W48 "diamond" exhaust manifold on 240Z?

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I have a 1970 240Z with the stock exhaust manifold with emission tubes in it. It is in a bad shape and I think it is leaking when heated up (sounds like a leak from one cylinder). I have a stock manifold from a newer L24e engine with the N47 head, and I am wondering if this manifold will fit the exhaust system on my car? I know it bolts right up to the engine, but is the outlet flange in the same position?  

It is marked W48 and looks alot like the 240Z manifold but without the emission tubes. 


I have tried searching for this everywhere, but can't seem to find an answer. 



Best regards,



Edited by Tomzern
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The later one is probably shorter from top to the collector flange.  Take a measurement.  It should fit the head but the exhaust pipes will be too far away, and and not aligned correctly.  You'd need to do some pipe work.


I did the swap yesterday and can confirm that the only difference between the stock 1970 240Z smog manifold and the W48 manifold is the bolt pattern on the outlet flange. 


Since I didn't find any info on this subject myself, I might as well make a little guide now if anyone else wants to do this :)


Here is a couple of comparison pics of the two types:


Stock on top, W48 bottom



The W48 manifold has larger runners compared to the stock one. Don't know you gain anything out of it though.



So here is how I solved it. on the W48 manifold the bolts on the outlet flange are 10mm instead of 8mm that the stock one uses. They are also placed further out from the outlet holes, but the pattern and size of the exhaust outlet holes are exactly the same as the stock manifold. I took of the collector pipe and cut the bolt holes out with an angle grinder to allow it to fit the new manifold. Then I mounted it in place and it all fit perfectly! :) I forgot to take pictures of the modified collector pipe, so here is a quick drawing that shows where to cut:








It doesn't look pretty, but it's a cheap and easy way to get rid of the smog manifold :)

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