I'm not sure if this is the right place to ask, but here goes.

I've looked at several 240z's locally that were '73 models, produced in late 72 and 73, and every single one of them has had what appears to me to be round top carbs. I've read online that 73 was the model year that the carbs went to the horrible flat tops, but since all of the ones I've seen haven't had them, its hard to believe that all the previous owners swapped them out for their round counterparts. So, is it possible that these 73's came with the round tops either stock or as a dealer option, or were they all aftermarket mods?

According to ZTherapy's Spotters Guide, the flat tops started in June 1972 and lasted through the 260. 1974.

Are there any other sources confirming that every Z from that point on received the flat tops? I haven't found anything other than the guide you mentioned.


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Possibly best advised to tag the line "....in the USA/North American market" onto your original question, as 1973 240Zs sold elsewhere in the world certainly did.

Yes sorry, I am referring to the US strictly


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50 minutes ago, Locke said:

Are there any other sources confirming that every Z from that point on received the flat tops? I haven't found anything other than the guide you mentioned.


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How about the Nissan factory parts manuals for North America? They clearly show the 3 types of carburetors and the timeframe of usage:

4 screw - through the 71 model year (ending Aug 71)

3 screw - for 72 only (Sep 71 to Jun 72)

Flat top - for 73 Jun 72 to Aug 

If you don't have a copy of the factory parts manual, you can order an electronic version from the store on this website. Proceeds go to support the site. 

 

Ah, I didn't even think to look there. Thanks for the help everyone! I guess that it's just a coincidence that I've only seen the round tops in person.


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 The conversion to the earlier round tops from flat tops was probably the most popular throughout the years. Now days, it's quite rare to see a late 72 - 74 with the original flat tops.

So related question:

The reason I'm so curious is because I'm looking to do a full restoration and would love to rebuild the original engine, and for some reason the issue of the round tops possibly not being original is not sitting with me very well for some reason. Do you guys think that putting round tops on a car that would formerly have flats detracts from any sort of "originality value" or am I just overthinking it way too much?


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Are you building a show car or a reliable driving car?  Round tops are soooo simple, even I figured them out pretty quick and that says a lot about the carbs and me. 

Ask member @Zupabout restoring a '73 with flat tops "properly".

Carefully sole search your desire to have a totally original '73 restoration before continuing. The issue used to be the difficultly of restoring the flat tops to original like new condition, but rebuild kits have recently been found and returned to the market making it "possible". Tuned and in-spec these carbs are 'better" than round tops !! (sorry, couldn't resist... please don't fill this guys thread with rebuttles...   )

PS, if you need some, I might have kept a few....

 

 

Thanks zKars, I'll check it out. I don't actually have a Z yet, but I was asking because I've found the carb issue to be making me hesitate to consider a 73 over an earlier model, even though there seems to be a lot more 73's available in my area.