A good way to measure the vulume of air/fuel taken in by an engine?
 

OK, so, from one of my posts in the motorcycle I have established that I am an idiot with a 2-3 horsepower bicycle engine kit who wants to soup it up. Granted this is not in the name of pure efficiency, but the people on this forum seam to be VERY knowledgeable and don't mind overly thorough, long winded posts.

Here is a link to that thread, please go there if you want to tell me not to hot-rod a moped:

https://www.gassavers.org/showthread.php?t=11166


Anyway, my main point:

I see a lot of potential into dumping extra gas- be it it pure oxygen from a small welding tank, propane, hydrogen, HHO- whatever I figure out gives me the most bang for the buck and is easiest to install on a bike frame, into the air fuel mixture. I figure the easiest way to measure volume released per given unit of time to simply hook a hose up to the compressed gas tank, attach the other end to a balloon tied to the bottom of a large (home made) graduated cylinder filled with water and measuring the displacement.

There could be some inaccuracy based on water pressure and the exterior pressure of the balloon. I am hoping that these are negligible, but if not, I could set up an air filled balloon in the graduated cylinder with the water above it and read the pressure with a barometer. I could then seal up the top of the cylinder and attach a vacuum hose to the top of it and add suction until the barometer/psi gauge reads at 1 atmosphere. I'm really hoping this is unnecessary though...

So anyways, this would allow me to set up a time frame, turn the gas tanks to different levels of "open" and see how much gas they release in that period.

My question is, how could I measure the amount of air my engine sucks in? My only idea would be to use a balloon setup where I build a sealed box around my intake, attach a balloon with a known volume of air to it, and run the engine at varying throttles. Anyone think this would work?

If I had both these numbers I could then know how much to lean the engine by (for propane), or how much to enrich it (for oxygen), as well as how much propane/oxygen/HHO I'd have to dump in as the throttle increased.

Can you vary the amount of HHO produced by current? Because that way I could simply have a voltage or amperage controller hooked up to the throttle to vary the amount produced to match the air/fuel intake of the engine. (PS, HHO cell run off a battery, charged at home, not off the engine, and not generated at home and then compressed)