From the 'net:
Emulsion Tubes
Emulsion tubes control the metered fuel and air introduced into the Carburetor. When air enters the emulsion tube through the air jet and fuel enters through the the main fuel jet this condition emulsifies the fuel delivered into the carburetor. The emulsion tube has a series of small holes from top to bottom which regulate the fuel mixture. These holes allow air and fuel to enter the main circuit and emulsify fuel. Low speed engine conditions or engines at idle do not require use of the emulsion tube or the main circuit. As engine speed increases the fuel level in the float bowl drops uncovering these holes and allowing air from the air jets to enter the main circuit resulting in a lean mixture. As the engine speed increases the fuel level in the float bowl continues to drop. This uncovers even more of the holes in the emulsion tube, which makes the air jet have a greater effect on the low to high rpm fuel delivery mixture.
When RallyBob jetted my 38DGAS There was a slight hesitation when you hit the throttle. (I barely noticed it) He said it was due to the E-tubes. I put the F-66's in and the flat spot went away.
Spell check... you noticed.
Emulsion Tubes
Emulsion tubes control the metered fuel and air introduced into the Carburetor. When air enters the emulsion tube through the air jet and fuel enters through the the main fuel jet this condition emulsifies the fuel delivered into the carburetor. The emulsion tube has a series of small holes from top to bottom which regulate the fuel mixture. These holes allow air and fuel to enter the main circuit and emulsify fuel. Low speed engine conditions or engines at idle do not require use of the emulsion tube or the main circuit. As engine speed increases the fuel level in the float bowl drops uncovering these holes and allowing air from the air jets to enter the main circuit resulting in a lean mixture. As the engine speed increases the fuel level in the float bowl continues to drop. This uncovers even more of the holes in the emulsion tube, which makes the air jet have a greater effect on the low to high rpm fuel delivery mixture.
When RallyBob jetted my 38DGAS There was a slight hesitation when you hit the throttle. (I barely noticed it) He said it was due to the E-tubes. I put the F-66's in and the flat spot went away.
Spell check... you noticed.