Ztherapy S.U. conversion

[rclayton12]

I have just bought a set of the S.U.s from Ztherapy for about $750 with the adapter for the air filter. They are going on a 73 240z that had the hitachi flat top carbs. How hard are they to install and what can I expect to encounter? anyone ever ordered theirs from ztherapy? How long does it typically take?

[ChrisA]

Hi Richard,

My 73 has ZT carbs. But I have the whole setup from a 72. Manifolds, air box, etc. Took me about 4 hours. Of course there was some beer drinking going on.

Some of the other members will hopefully chime in here. I've heard there might be a spacing issue between the carbs using the Hitachi manifolds. But I may be all wet on that. I remember member "beandip" saying that the connector linkage between the carbs needs modifying.

Try searching the forums for better answers than mine, I know they're there.

Much luck,

Chris A.

[Fun_in_my_z]

The carbs should come with a Video that will help you. I have a extra set of round tops with most of the linkage. The carbs are pretty much shot but if you need linkage parts let me know.

[RAZ1]

I have the correct manifold that you need. You would have to find the linkage stuff but you will have the manifold and balance tube. Your cost? Nothing, just let me know you want them and it's yours. I feel like giving today.

Art

[alordzot]

Reading the posts brings up a question on my part. I have 2 sets of round tops and the manifolds are still attached. Should I replace the manifold that is currently on my 73 when I do the swap out?

Thanks

ZOT

[Dtsnlvrs]

Whatever any of you do, KEEP the 73 and 74 manifolds.....just replace the balance tube with the earlier style. Nissan changed the casting on the later cars to improve the combustion mixture in cyl 2 and 5....if you doubt this....look down an original 70 intake and tell me how much intake you see for 2 or 5 then look down the intake of a 73 or 74. Dont know how much HP gains could be had but will say from experience that all 6 plugs will read the same as opposed to 2 and 5 being "off"

[ZSaint]

I used the N36 manifolds for my 3.0. I was told the same info about the manifolds. I have not seen anyone do a dyno test to see if these manifold flow better. They look better and seem to have more flow but no one will give me any dyno results to show they are better. I guess we will continue to believe that they are better.

[d.a.thomas]

glad to see that you bouhght the "complete"set-up.i had purchased reworked

throttle bodies(only) from z-therapathy(for my 6/72 L-28 n-42 engine)did you get new(looking)springs and things?

[Pop's Z]

I just replaced my old round tops of undetermined age(on my 73) with a set from Z therapy. I got the linkage and new springs. What a difference!!! I took a run up into the mountains yesterday and the car seemed transformed. Power on after1500 rpms and no hesitations to 6000rpms. They also gave me different needles (at no charge) as I live at 5000 feet here in Colorado and most of my driving is done at higher altitudes. It may be my imagination, but the exhaust smell seems less obnoxious. It was not a hard thing to do and the video is very thorough and if you have problems Bruce at Z therapy is always helpful if not always available but keep trying.

"Be happy in your work"

Mike G.

[Dtsnlvrs]

Now if only my triples were that easy

[sakijo]

I bought the whole kit too. Still in the box though. Yes, new gaskets, hoses, new or replated linkage and springs.

[rclayton12]

Yes came with replated springs, center linkage and everything. I have mounted them and have got it running. I need to get the timing checked because it is definately off. Does anyone have any tips on cleaning up the 240/260 balance tube?(clearing and jb welding all of the emission things) Has anyone removed the exhaust gas reticulation valve on thier z??