Flat top carbs

[RIP260Z]

Hi,

I am starting to think about my long term project, a late 260z (over here in the UK), and I am going completely standard, thus including flat top carbs. Yes, I want to use then, not bin them and put on round tops. Why, the late 260z is getting so rare here, and a standard one is even rarer. So, I am asking has anyone got any tips on using these carbs, refurbishing, tuning, things to watch out for. I have yet to ask the UK Z community, but since the US was the biggest market, someone must like using them.

Cheers

Ian

[Montezuma]

I got a spare set of square tops that came off my low milage 73. Let me know by PM if you are interested in them.

[sblake01]

I liked using them in the past but that's an unpopular viewpoint here in the U.S. The U.S. version flat tops were emissions carbs and people here don't have much interest in them. Their solution is to throw them away and replace them with the famed "Z Therapy" round tops. We did a few of them back in the 70s and 80s with some success but the parts are becomming harder to find here. I understand that the non-U.S. flat tops are different and you might have better luck asking around in the U.K. since there they would have a better insight into the carbs used there.

[RIP260Z]

Thanks Stephen,

Its the same in the UK there is more interest in swapping the emmision flat tops for the su type. I would have done the same, but since I want to be standard, it defeats the object. But I thought I would ask anyway, as you never know until you ask. Why did you like them?

Montezuma, thanks, but as people get rid of them like in the US, you can pick them up cheaply here.

Cheers

Ian

[sblake01]

I didn't particularly like them over the round tops it's just that a friend of mine and I were able to get them to work satisfactorily. As I recall, it involved some drilling, machining, filling and basically eliminating the emission aspect of them. I had a set on a Z, a 510, and a 620 and they worked well. He still has a Z shop to this day but he doesn't do much with them anymore due to the lack of parts needed to work on them.

[Zedrally]

I'm running flats on the 260, purely because it's authentic.

The only work that I performed was to overhaul them totally.

A complete strip down and re-build. I doubt that it can be done now as the re-build kit is NLA.

As I've stated in previous thread, they work fine, infact better that the round tops that I have on the 240, go figure that one out.

My advice, to stay original use the flats, but only after you have re-built/conditioned/overhauled them.

Good luck and let us know how you go.

MOM

[RIP260Z]

Thanks Mike,

When I get round to it I plan to completely strip them which will help a lot. As the rebuild kits seem to be NLA, I better keep my eye for any New old stock..

Cheers

Ian

[Zs-ondabrain]

I also have a set of flat tops. But I'd have to remove the chain after pulling them from the water. Who'da thunk you could use my boat ankers as carbs for a 260Z? :stupid:

[Zedrally]

I just remembered that the only kit I could find was Fuel Miser, not sure of the availability, perhaps you can post back if you manage to find a set?

[RIP260Z]

Have asked my contact here in the UK for service parts to purchase now so I am ready in a few yrs time to rebuild them. He has gasket kits, nozzles and valve assemblies, he thinks, maybe needles and other misc. bits for flat tops. Will have to see what I can get. My next job is to take the old needles out and see what number they are.

Cheers

Ian

[rclayton12]

I ran the flat tops on my '73 and they worked fine untill they needed a rebuild. I rebuilt both of them with a rebuild kit from oreillys and lots of berryman carb cleaner. Taking them on and off was the hardest part of the project. Just be careful not to tear up the tops of the screws, because they somewhat hard to remove. Vise grip pliers were very helpful.

[RIP260Z]

Zedrally,

If you are interested, I have managed to get hold of:

16455-N3311 Gasket kit x2

16354-N3310 (which I think is the correct part no. ) needle N66 on order from Japan, and I have a set of N57 and maybe able to get a pair of M76 and M87 needles.

16466-N3311, Piston choke

16101-N3605 Valve 1.7

16496-N3300, Nozzle

Also a pair of top dampers (where you put the oil in) air filter to carb. gasket a few air box bolts and an metal assembly tube (did not write part no. down).

The only things listed with a price were the gasket kits and the N66 needles. The rest had prices that were current 10 yrs ago.

Cheers

Ian