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Compression Ratio

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Old Mar 24, 2011 | 12:28 PM
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Default Compression Ratio
Can anybody tell me the end compression with 9.5 and / or 10.5 pistons when using unworked SE heads (9.5-1)??
 
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Old Mar 24, 2011 | 12:57 PM
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Try this,

http://www.bigboyzcycles.com/TwinCamComp.htm
 
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Old Mar 24, 2011 | 01:25 PM
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Originally Posted by swensos
Can anybody tell me the end compression with 9.5 and / or 10.5 pistons when using unworked SE heads (9.5-1)??
I noticed in a previous thread you were talking about using an EV-27 cam. Don't use that cam with high compression pistons. It builds up too much cranking pressure. Send Andrew's an email asking them what cam they prescribe for your build. If I remember correctly they told me an EV-48 but I went with a Crane cam instead.
 
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Old Mar 24, 2011 | 01:37 PM
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Default not doing ev27
I'm going to use Comp's Vthunder once I figure out the end CR #'s probably the 3030
 
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Old Mar 24, 2011 | 01:49 PM
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Originally Posted by swensos
I'm going to use Comp's Vthunder once I figure out the end CR #'s probably the 3030
I looked up the v thunder 3030. Sounds like a good choice.
 
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Old Mar 24, 2011 | 02:17 PM
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Originally Posted by KumaRide
that calculator is out of my league..
 
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Old Mar 25, 2011 | 06:31 AM
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Originally Posted by swensos
that calculator is out of my league..
My suggestion is to not worry about the final compression ratio. As long as you pick the right cam for your piston choice, you'll be fine.
 
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