OM616,

The report I was referring to was NACA-tn-436

http://aerade.cranfield.ac.uk/ara/dl.php?filename=1932/naca-tn-436.pdf

I'll post more on this later but right now I'm in a pinch for time.

Until then here is a few things I have learned from reading stuff written by Harry Ricardio (the inventor of the prechamber and swirl chamber engine)
To get the most out of a prechamber engine you want most of the combustion to occur outside the prechamber. For a prechamber engine to work correctly you must have a restriction of flow. There is an optimum speed of swirl. To slow and there isn't enough mixing. Too fast and heat is scrubbed of to the chambers walls.

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green 85 300SD 200K miles "Das Schlepper Frog" With a OM603 TBO360 turbo ( To be intercooled someday )( Kalifornistani emissons )
white 79 300SD 200K'ish miles "Farfegnugen" (RIP - cracked crank)
desert storm primer 63 T-bird "The Undead" (long term hibernation)

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