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Float-less carbs with interchangeable jets, but NOT FI?

Maybe something from the bike world?

Need to create an IR intake system for a Buick V6.
Have very little space under the bonnet and not enough room on top of the manifold for IDF's or IDA's.

Would like to mount them with the throats vertical or nearly vertical.

Might be able to mount them horizontally and allow floats but that means LONG runners or a poor intake tract design.
Want very strait runners.

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If I must be a one-man PC free zone, so be it!

What is a floatless carb? Since a carb is generally defined as using a venturi to meter the gas by air flow, a pool of neutral pressure fuel seems like a requirement. Are there carbs that do that without a float?

John

Hello Richard
You contact Dan at http://www.danstengineering.co.uk/

He fabricated an intake manifold for me to adapt Suzuki GSXR carbs to my Toyota 4AGE engine.
cheers
Doug

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book 4AGE build, Supra W58 transmission, Corolla GTS live axle

Wal Philips fuel injectors are the closest thing i've seen to a floatless carb.

they rely on head of fuel and a spindle and sleeve syncronized with a throttle plate to regulate the incomming mixture.

here are some pictures, the first one is from the early 70's showing a triumph twin powered junior dragster these were very popular in England at the time as a development of a go kart just for drag racing, in the mid 80's, a kawasaki powered one would run the quarter in low 8 second passes.

the one shown has two wal philips injectors gravity fed from two s.u. float bowls to provide a head of fuel which were in turn fed by pressurized fuel from a tank, this weird system was to feed the little car 50% nitro/methanol mix, virtually a top fuel bike engine.


the next shows a ford v6 with a twin throat injector and barrel valve but this time fuel is metered in a gallery inside the device to feed all 6 cylinders via small tubes and nozzles installed in the manifold ports and is fed by a constant pressure electric pump.


to achieve proper fuel control two barrel valves were used one to feed more fuel to the engine as the throttle was opened and one to return fuel to the tank as the throttle was closed


the last photo shows highly modified s.u. carbs without float bowls where fuel is supplied directly to the bottom of the main jet but metered by means of the needle obstructing the jet when the throttle plates are closed and opened as the throttle plate open by means of the vacuum piston which syncronizes the fuel and air.

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A possible option would be carbs off a snowmobile that has a large 38-40mm choke. But the cost of 6 carbs and the mount tubes plus the building linkage , it would probably be easier to build an EFI system with log design manifolds for each bank and mount two throttle bodies at the front of the engine. Dave W

Wal Philips fuel injectors, that bring back memories. Tried one of those on a Lambretta scooter, just a joke jetting would change with fuel level, so during a single tank of gas it would run well for about 10 minuets. That make an Amal Concentric look like a sophisticated device. If am Amal Concentric is a controlled leak and Wal Philips is a poorly controled leak.

Graham

Pumper carb, Tillotson, Mikuni, or Wallbro, etc, used on snow machines and ultralight aircraft.

EFI would be close to same money (MegaSquirt).

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Honey anyone?

The thought came up as I recall an Italian (?) bike carb that used a remote float and still worked well.

Would not expect bike or snowmobile carbs to be that expensive.

38 C.I. per cylinder so not sure bike carbs are large enough.

Wanted Webers but not enough room for them.

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If I must be a one-man PC free zone, so be it!

Interesting but a V engine is a bit harder.

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If I must be a one-man PC free zone, so be it!

dude, search harder. there's have been plenty of vertical - or near vertical - throat motorcycle carburetors manufactured since the early 80s. my 1985 Honda VF700 had four carbs, two horizontal and two vertical throat in the crux of the V4. My 1993 Suzuki VS1400 had a vertical throat carb for the fwd cylinder.

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The B-3 build log: http://www.locostusa.com/forums/viewtopic.php?f=36&t=13941 unfortunately, all the pictures were lost in the massive server crash

The beginnings of the Jag Special,
https://www.locostusa.com/forums/viewtopic.php?f=36&t=19012
Again, all pictures were lost.

Look at the Suzuki SV650 1st gen. V twin with 2 downdraft carbs, the 2nd gen is injected.

Graham

David Vizard was fan of making floatless carbs for the Pinto 2.0. I believe he used a return line in the float bowl which had foam in it to control sloshing and an electric fuel pump on the return line.

Bill