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Old 10-23-2009, 08:39 AM
OLD_SLOW and in the WAY
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Default ** Update pics 15% power gain with resonator

the units i tested have a 355ml volume ( as reference it the same volume as a 12oz pop can) with a 3/8" diameter intake horn by 1" long, the horn can be anywhere on the resonator. basically it uses the spitback to help charge the resonator box and the inertia of the incoming air through the smaller opening overcomes the spitback which supercharges the next intake cycle. the engine comes on like a nitrous shot. the shape of the resonator isnt critical as long as you have 1" between the carb opening and the resonator wall, you will have to have the intake runner lenght set at 3 13/16" from piston face to carb opening. the resonator will give you some insurance in a dunking by keeping from gettin hydro'd.
nevermind the aluminum chips it was in the construction stage

here are the only pice i have left of the "ratflask" hemmholz resonator.
the container was made by rubbermaid and had a very tight seal with the lid.

this is the velocity stack used inside the flask

inlet horn and grommet

interior of flask

profile of intake stack, the 5 to 8% refernces the gain over a straight carb opening

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first pic is the inlet horn starts as 7/16" brass tube but after it gets flared the diameter shrinks to just a tad smaller.

the following pics are different flasks i tried

this flask was made from the stock zenoah air filter housing although sealing it was quite a challenge

this last one worked out very well it was halon fire extinguisher bottle, volume rt at 355ml

the easiest way to shape a custom flask is to buy a cheap candle just slightly larger than a pop can, melt this wax in the container, when it gets cooler and mushy then you can hand form it to the desired shape.

i am no longer in the biz so youz guyz are on your own if you want one