# Flow Rate Thru Differnt Size Holes

As you can see, each successive hole is twice as big in diameter as the preceding hole. In row one, is the flow of rate through these holes at one PSI. The eight digit number is the area of the whole directly above in the first line. Below the a digit number is the area difference between each hole. Below that is the tested flow difference between the holes. As you can see, successive hole is four times the area of the previous hole. The last line is the flow rate through the whole above and you can see the flow rate is approximately four times the rate of the previous hole, within a small margin of error in some cases. About .1%

What determines fuel flow rate? How is it adjusted? I’m assuming it’s a constant pressure and that throttle varies size of opening rather than rate of flow?

Does increasing the fuel flow by enlarging the hole decrease detonation efficiency?

“Big” books have been written on the subject. “Detonation” leaving off the efficiency, I’ve never heard that term used in this context before, is caused by excessive heat “and/or” pressure. If the carburetor is working (pumping) at the peak of its capability, and you’re still getting detonation, drilling the fuel passage holes will probably help. As the air fuel ratio gets leaner, it burns hotter, more fuel will cool it down.

I’m probably using the term wrong. I guess what I’m asking is it seems you are showing a 4x multiplier as you increase the hole.

At some point, you must experience too much air/fuel and things go awry. Is the point that there’s a potential increase in output if you wanted to mess with this but it’s theoretical because you actually have to consume all the fuel fully?

Sorry I am not a mechanic, just driver. But I find this interesting.

This is only an example of the difference between hole sizes and the amount of fuel they can flow at a constant pressure. Each hole is four times the area of the previous hole, this works out to four times the flow of the previous hole. It has nothing to do with carburetors other than showing that increasing the hole diameter increases the flow linearly. Each hole has four times the area of the previous hole, and four times the flow, approximately, very close.

Got it thanks. 20chars

4x the hole size, and less drag at the boundary layer relative to the increase in cross-sectional [flow] area.