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Those two are vents. Run tubing up to the airbox and leave them open.
Steve

When the carburetors are installed on the 1981 KZ650-CSR, the vent tubing is open to the atmosphere, and routed over the airbox shoulders & fitted snug between the frame & side covers so that water won't get in.

Since the carburetors are going to be installed on a car, you don't have to do anything about the air switch valve or Kawasaki clean air system, since the VM24 carbs don't have any vac ports.  the ports are on the carb holders.

ps: does the car have a tiny engine?
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Ok, Ill be running pod filters, so Ill vent them to the atmosphere, maybe put a short length of hose on them. I didnt think they had vacuum ports so reading about the switch valve threw a wrench at me.

The car is a 87 Honda Accord, it has a 12v 2.0l. People commonly run a weber 38/38 dges, a few do weber 40 or 45 dcoes, which a way too big. Ive talked to several guys that have used carbs from later model 600cc bikes, usually in the mid 30mm range, still pretty big. Vm24ss's are probably the smallest anyone has used, but 4 of them are heads bigger than the factory carb. Stock carb has a ~30mm secondary and I dont think the primary is even 20mm. Its hard for them to be too small, and at least these have a good range of tunability, but no, I wouldnt say my engine is exactly tiny.

Also, I think I measured the spigot end of these carbs at like 28mm the other day, which I dont understand if theyre vm24ss's. Was planning to remeasure them tomorrow anyway. If theyre the last carb on this list kz900.com/carburetors.html it would make sense because I thought the needles were 5dl31s lol, but if thats the case I have admittedly become lost in the forums and manuals.

How did you come up with that 5DL31 number for the jet needles? Are you guessing or assuming or what?
The carburetors in your pics appear to be the stock VM24s for the 1981 KZ650-H1 CSR.
The ribs on VM24 carbs are kind of distinctive & that's one way to distinguish them from the larger VM carburetors.

Measure inside the carburetor bore near the throttle slides >> VM24s should be 24mm there.
At the engine side lip, I'm pretty sure they measure a tad more than 26mm ID. 

I asked about the tiny engine because I've only heard of VM24s being used on a KZ750-4.   For a larger Kawasaki I think the carb spacing is wrong, but I had assumed they'd be too small anyway. so perhaps I'm wrong about that.  I don't know that much about it, but I was thinking they'd be too small for most automotive engines, even 2.0Ls, but apparently I'm wrong about that as well.  For a car I would think CV carbs might be better for more horsepower. but what do I know. not much.
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They are vm24s, Im just going nuts, busy week. 24 near the slide and opens up some near the end. I had the specs of the 5dl31s and I measured the needles it came with, they were within a tenth of a mm everywhere on the needle. Ik a tenth of a mm makes a difference, but theyre being rejetted and used on a different entirely anyway, the 5dl31s come in similar carbs and I couldnt buy any of the stock needles that were listed, so Id say theyre my best choice. Aside from being within a fraction of a mm different in diameter, they were also the only ones that were even remotely the same shape.

They arent for high hp, its a 12v honda for gods sake lol. Theyre just decent, available, and a totally unorthodox way of improving, which is the only way to do a classic Honda. Worst case scenario I port them one day when Im bored, at least on the outside ends where Ill probably make no difference, then when that doesnt work I find some bigger cv carbs.

If I had re-read about the jet needles in an earlier reply of yours above, I would have seen that you bought them. doh.



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Yeah, I couldnt use the stock ones, one was bent pretty bad