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Pre combustion chamber design research


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Hopefully I am not going backwards, I am having a set of the military triple square ID ones opened up to match the diamond just on the opening no machine work to the internal side of the cup, Head gasket to lower compression to 18:1 or so.
We haven't done the testing to prove which cups are better yet. But though everything I've posted here and tons of other stuff I've been reading. I dont see a reason to run bigger cups at all. Every one always talks about bigger cups can flow more fuel. Well even if your pushing 300cc of peak fueling. That's only .3cc per injection event. Small cups can handle a mouse fart amount of fuel. The big factor is going to be getting a pressure transducer in the prechamber and seeing what effect each cup has at a given RPM. The only benefit I could see with bigger cups is the ability to be less restrictive at high RPMs. But that restriction is needed for atomization of the fuel as it leaves the cup. Alot of testing to come. I'm behind schedule on where I want to be. But this is still very much in the works. Just need to let my bank account recover after dropping some serious cash on a bullet proof rotating assembly from TSP.