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How sensitive are SU's to bowl angle?

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I've figured out a way to tilt the bolws on my euro 1500 carbs to get them to clear. I planned on raising float level to compensate for any volume lost due to the tilt. The only problem I see is maybe a hard left hand turn shutting fuel off, but it really should be no different from fuel climbing the bowl wall and closing the float off.

Are these things super fickle?
 
Remember the float level determines the height of the fuel in the jet.
 
I saw those. I memeber offered me some for $50 shipped.

Trev, please do explain. I haven't played w/ any of these yet and don't know squat about them. I guess I should do a bit of reading up.

Somoene once recommended a book, but I can't rememebr what it was and can't find the thread.
 
The fluid level in the bowl is the same as the fluid level in the jet. If the fluid is too high then the car may run lean (unless it is way too high then it floods). If the fluid level is too low, then it will be rich (unless it is way too low and then it will be immensely lean).

The ability of the low pressure area in the carb to draw up and atomize the fuel requires the fuel level to be within a certain distance from the throat. If it is too far away it can't draw up enough, too close and it draws too much.
 
Did you misspeak and state the opposite of what you meant? I would think that a fuel level too high would make it easier for the low pressure to pick up the fuel making a rich condition rather than a lean one. And the opposite with a too low fuel level. Or is there something that I am not taking into account?
 
Westfield_XI said:
Did you misspeak and state the opposite of what you meant? I would think that a fuel level too high would make it easier for the low pressure to pick up the fuel making a rich condition rather than a lean one. And the opposite with a too low fuel level. Or is there something that I am not taking into account?
Click to expand...

I was thinking the same thing.
 
Nope. Subtle changes in fluid level cause a rich/lean condition based on the needle profile. More drastic changes cause opposite rich/lean condition based on distance the fuel must be carried.
 
my experience is that they aren't fickle at all - don't forget on hills you are already changing the angle. depending on which axis you are moving the bowl, there are any number of bowls available precisely for different angles.
 
JPSmit said:
my experience is that they aren't fickle at all - don't forget on hills you are already changing the angle. depending on which axis you are moving the bowl, there are any number of bowls available precisely for different angles.
Click to expand...

Actually, all the bowls are the same, some of the lids are oreintated differently, the rubber grommet between the float bowl and carb body is what sets the angle of the float bowl and there many different types of those.

I'm not that wise on these Euro twin HS4 set up on the Midget 1500, but one way to buy clearence would be to mill the spacers thinner, and shorten the studs, depending on how much room you need, of course that will move everything , linkage and such closer to the engine/heatshield.
 
if it'll help i have a haynes su workshop maunual that your welcome to use if you want to ship it back and forth...
 
kellysguy said:
No spacers, they bolt directly to the manifold.
Click to expand...

Oh well, so much for that :smile:, I guess it the footbox mod then, which does not seen to be too elborate.
 
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