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References are often made comparing the bathtub type combustion chamber to the hemi type chamber - ie; SE HTTC CNC heads with the hemi type chamber as compared to the bathtub type chamber with flat top type pistons. Can anyone supply more info on the diffirences - characteristics and performance benifits of either / or..

Thanks - Tom
 

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chambers

Well, I would think if your going with the Hemi chamber and piston there would be more turbulance from the high dome on the piston, But could also hurt flow and forsure the flame travel is not going to as good. A flat top piston is:whisper: always going to give a better flame travel as opossed to a dome piston.
 

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According to many experts flat tops have a faster flame travel-less prone to detonation. With the panther piss that's called gasoline these days, flat tops look better to me.
 

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Well in the shovelhead and Pan era those Hemis had no quench and dead area on the non-spark side. Today when Axtell machines the chambers 20° for their pistons and sets the quench tight the dome takes less prasitic loss to compress the mixture compared to a flat top and also induces swirl and tumble, all good. Their pistons are flat after the quench ring or slightly dished depending on the CR and displacement.
This setup has the potential to exceed the flatop scenerio but is more difficult to optimize. I like flatops whenever possible and the Axtell setup would be the another alternative I would consider.
 
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