CrackedDSM
10+ Year Contributor
- 3,472
- 2,625
- Dec 17, 2009
-
Pensacola,
Florida
Alright, so I've been doing a little research on my current piston setup and need some answers. From someone either knowledgable about this subject, or with personal experience using these pistons.
I asked my machinist for 9:1 pistons on my built long-rod 2.4, and the pistons he provided me with he said were 9:1. But I searched the part number (K627M87AP) and it comes up as Evo pistons. They said 9:1 on an Evo, but Evo's use 43cc combustion chambers. Everything I've found said these should be 8.5:1 on a DSM.
However I was sifting through ExtremePSI and found this. http://www.extremepsi.com/store/product.php?productid=21528&cat=1586&page=1
I used the information listed there in a compression ratio calculator here http://www.gtsparkplugs.com/CompRatioCalc.html and it gave me 8.82 to 1 compression. I used .011 Piston-to-deck height in my calculations though and I'm unsure if that's proper or not.
Any thoughts/experience/advice would be awesome. Will these be 8.5:1 or 8.8:1 like my math shows?
Edit: Did a little more digging. I'll check back in later with my actual deck height clearance and compression once I do the measuring.
I asked my machinist for 9:1 pistons on my built long-rod 2.4, and the pistons he provided me with he said were 9:1. But I searched the part number (K627M87AP) and it comes up as Evo pistons. They said 9:1 on an Evo, but Evo's use 43cc combustion chambers. Everything I've found said these should be 8.5:1 on a DSM.
However I was sifting through ExtremePSI and found this. http://www.extremepsi.com/store/product.php?productid=21528&cat=1586&page=1
I used the information listed there in a compression ratio calculator here http://www.gtsparkplugs.com/CompRatioCalc.html and it gave me 8.82 to 1 compression. I used .011 Piston-to-deck height in my calculations though and I'm unsure if that's proper or not.
Any thoughts/experience/advice would be awesome. Will these be 8.5:1 or 8.8:1 like my math shows?
Edit: Did a little more digging. I'll check back in later with my actual deck height clearance and compression once I do the measuring.
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