Guest Anonymous Posted July 15, 2002 Share Posted July 15, 2002 since so many people have told me the flat top carbs are crap and since i cant get mine to stop shooting gas into the air filter i was wondering how hard it would be to put 240 round top carbs on my 260. do i only need the carbs or also the intake manifold, also what kind of problems would i run into regarding the vacum lines, as im assuming the 240 has fewer than the 260. Quote Link to comment Share on other sites More sharing options...
Lockjaw Posted July 15, 2002 Share Posted July 15, 2002 YOu need the carbs, linkage between the carbs,aircleaner, and the balance tube would be nice too. There are after market Air cleaners available as well. Rumor has it the 260 intake manifold is worth 10 hp over the 240 one. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted July 16, 2002 Share Posted July 16, 2002 fairlady 327 did it with just the round carbs on a 74, of course its ugly as hell with plugged vacum lines- but it was worth at least 10hp over those rotten flattys. Quote Link to comment Share on other sites More sharing options...
Boobala Posted July 16, 2002 Share Posted July 16, 2002 On my first '73 240Z I swapped the entire intake, carb's and linkage from a '72 240Z. ('73's have same basic carb. setup as '74 260Z's) It was very easy to do. Only took an hour or so, and it worked perfectly. There are several early SU setups on eBay to choose from. http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=1843906331 http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=1843588245 http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=1842754558 Quote Link to comment Share on other sites More sharing options...
Guest bang847 Posted July 16, 2002 Share Posted July 16, 2002 David!!! these are some good deals on carbs... Quote Link to comment Share on other sites More sharing options...
Boobala Posted July 17, 2002 Share Posted July 17, 2002 Don't forget www.ztherapy.com These guys can make your SU's better than new. Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted July 17, 2002 Share Posted July 17, 2002 I agree with Bang. I didn't know the early SU's were so common or cheap. One word of caution. You need to make sure the carbs you are getting are rebuildable. The throttle shaft bushings tend to wear causing a lean condition at idle. I had just this problem on my 70. The lean condition caused some pinging which required me to use high octane gas. I found a place in LA that said they could replace the bushings, but it was going to run $500 or $600 to do. For that price it made more sense to get the smog leagal dual Webers from MSA. If I had it to do over again, I probably would have rebuilt the SU's. The Webers are nice carbs (a progressive 2 barrel with an honest to god accelerator pump), but the J bend adaptors to plumb them into the sidedraft intake manifold tends to puddle fuel when idling with a cold engine. Besides, the SU's are just too cool. FYI. MSA sells "rebuilt" SU's on an exchange basis for $600. You could buy one of the ebay set ups to get the carbs and all needed linkage. Once they are installed and tuned correctly, spray some starting fluid around the throttle shaft bushings. If you see a change in idle speed, then the carbs need to be rebuilt. You could then use them as cores for the MSA exhange (or find a local shop that can do the work for you). Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted July 17, 2002 Share Posted July 17, 2002 i checked out ztherapy, not only was it confusing but the product that it looked like i needed was 900 bucks, i dont have that kind of cash and if i did i wouldnt worry about the carbs because there would be a 350 sitting there. i appriciate all the info though, even though i hardly understand any of it, i just want to get the thing to stop flooding so i can sell the car. Quote Link to comment Share on other sites More sharing options...
Lockjaw Posted July 17, 2002 Share Posted July 17, 2002 No, all you need to get from Z therapy are the rebuilt carb bodies for 175 bucks, maybe the sm needles and new nozzles, and the video. Then transfer all your stuff from the su's over to the new Ztherapy bodies and go. The 900 deal is the whole shooting match, and they are charging that becuase they are doing all the leg work. Buy a set on ebay or whatever, with the whole setup, and then go from there. Then just bolt the carbs on your manifold, and keep the 240 one for a spare. You may not need to rebuild the carbs yet. Watch the video and you will become an expert at messing with SU's in a hurry. I am waiting for my nice K&N's to get here and then I am going to find some velocity stacks to go in there. I have the 260 intake too. Quote Link to comment Share on other sites More sharing options...
Lockjaw Posted July 17, 2002 Share Posted July 17, 2002 Or if you want to try an fix your carbs, take it to the Z doc. I think he is in richmond or somewhere like that. They know what they are doing. Quote Link to comment Share on other sites More sharing options...
Boobala Posted July 19, 2002 Share Posted July 19, 2002 New on eBay today: http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=1844922785 Quote Link to comment Share on other sites More sharing options...
Lewis Maudlin Posted August 8, 2002 Share Posted August 8, 2002 Some rebuildable SU carbs on ebay. I also have a good set with intake that ran well 1 month ago for considerably more $$$. http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=1849123343 Quote Link to comment Share on other sites More sharing options...
RB26DETT Posted August 8, 2002 Share Posted August 8, 2002 Hi Dangerboy, I've recently done this carby swap myself also, as the flat tops in my '77 260Z kept squirting fuel out of the front nozzle also. I used the complete intakes and carbies that I took of my '73 240Z engine. Try and get a complete setup, that way there is no messing around, just bolt up the intakes to the head then some fuel lines to the fuel bowl of the SUs, then it should all be sweet (after you tune the carbs!!!) Something that others haven't said, I found that I needed the metal rod which links the throttle from the carbs to the firewall from a 240Z as this bit is actually longer that those on the flat tops. As for the pollution gear, all that can stay off as the 240Z set up doesn't need it!!! You may also need to get a plug to block up the hole in the exhaust manifold if you are using the 260Z manifold and taking of the pollution gear. Good luck. Quote Link to comment Share on other sites More sharing options...
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