Calculate compression ratio help

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Mar 17, 2008 | 11:37 PM

firehawk618

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From: Marysville, WA

Calculate compression ratio help

-28cc dish piston
72cc heads
4.0" stroke
4.030" bore
not sure on headgasket thickness...

this is about all the facts I have...

I come up with about 8.3 cr

Is this close?

Mar 17, 2008 | 11:55 PM

KTamez

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From: Yakima, WA

I came up with 8.8:1 using a .030 Gasket, and assuming a zero Deck Piston Height.

http://www.rosspistons.com/calculator.php

Have Fun!

Mar 18, 2008 | 12:31 AM

Mr.MartyStone

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From: Screwston, TX

normally you'll have .005-.010 out of the hole, and with a boost motor I'd use a MLS .055" gasket. Also since you are going s/c I would shoot for around 9.5:1

Marty

Mar 18, 2008 | 02:19 AM

99blancoSS

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From: ST Helens, OR

So your going s/c with the 440?

Mar 18, 2008 | 02:50 AM

firehawk618

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From: Marysville, WA

S/c 408

Mar 18, 2008 | 06:49 AM

WAHUSKER

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From: Marysville, WA

With my -14cc pistons & similar setup plus .050 gaskets we figured 9.3 so I would think yours should be 9-ish like Kurtis posted. Sounds good for 15 psi.....