Radial engine carb position

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In the automotive lines there is a carb capacity calculation. I’ll have to look it up but I think for this small displacement it might not apply. I’ll find it and run numbers. One thin* we don’t have is the rated flow of the carb in CC per minute. It’s easy to say I have a 750 cc Holley carb but these smalSmall engine carbs just aren’t rated other than motors they were used on. Since these motors run on the carb specified, it would be hard to change without experimenting on an existing engine
 
I looked up the automotive calculation for carb com to motor size but I didn’t have even a bore size for these carbs so it’s just a guess.

way back I used the larger Perry carbs an large OS carbs on my hot rod air planes. These had fuel pumps and the motors had tuned pipes. They ran about 18,000 rpm on the ground probably much faster in the air. They were only .45 cu in so much smaller Displacement but far higher rpm ado they burned nitro an alcohol fuel so had larger air requirement than standard glow fuel. I think.
I saw somewhere that a model 700 is used on the 18 cylinder motor. The intake and exhaust systems are far from tuned and actually pretty snakey.
So not very efficient. I don’t have any idea of what volumetric efficiency is but it probably is not very high. My airplanes were incredibly fast for the era I usually burned a pair of glow plugs per flight and several gallons of fuel per day. I’ve already looked into building a dyno for these motors. But it would be necessary to keep my image and reputation. LOL. I’ve even looked into a water alcohol injection. They did have these so it would be fitting to model a system. New cars have plastic intake manifolds so I could see possibly having one 3D printed. I’ll know more about this as I get into the cad models. There just won’t be a real supercharger. It just will not scale other than looks.
 
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