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Old 02-09-2019, 09:48 PM
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1QwkSport2.5r
 
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Originally Posted by the Wasp
1QwkSport2.5r, can't he get his compression ratio by CC'ing the head, I did it on my Chevy 350 boat engine I rebuilt back in the early 2000's. it was pretty easy, all I did was leveled the head, and took a thick, clear piece of plastic, drilled a hole in it and placed it over the combustion chamber, and used a syringe to fill the head, and I kept track on the CC's as I filled the head. there is a calculation to convert the CC's to the ratio

Jim
He would need to determine combustion space in the cylinder and the head and follow the equation to determine the CR. The CR isn’t the entire story though - heat range of glow plug has a LOT to do with it. I believe the CR equation is head volume + swept volume / head volume.