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Discussion Starter · #1 ·
Hello all.

I was looking at the stock specs for my EVO motor and according to my service manual the stock bore is 3.5" inches aprox, and the stock stroke is 4.250" inches. I was taught that the cubic displacement of a cylinder is the area of the piston times the stroke, or the dia. times 3.1416 times the stroke. When I did the math I got 46.7313 per cylinder or 93.4626ci. Is there something I'm not taking into account?

Signed

Confused:confused
 

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Area = 3.1416 x r^2 = 9.62


Circumference = 3.1416 x d


9.62 x 4.25 x 2 = 81.77
 

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Discussion Starter · #3 ·
Thanks.

Was using formula for circumference rather then area. That's what I get for doing math on allergy meds.

Jonathan
 

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Discussion Starter · #5 ·

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Wayward Son
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Was always told Bore x Stroke x 2 = CI.

Start throwing the "r" into it and you lose me.

But tell the truth Jon. You were hopinh someone screwed up and you has a stroker. :nod
 

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Discussion Starter · #7 ·
Was always told Bore x Stroke x 2 = CI.

Start throwing the "r" into it and you lose me.

But tell the truth Jon. You were hopinh someone screwed up and you has a stroker. :nod
Yes a stroker would be nice, but that would leave me with two questions. One would be "where's all the power that comes with it?" and two would be "If I couldn't trust my factory service manual to get the bore and stroke right how would I be able to trust it with any of it,s specs.?" Kainam was right and I knew that as soon as I read his reply. Cold and allergy meds always make me loopy. BTW Labor Day is this weekend and so is a lot of 12 oz curls for me and my buds :drunk so please ignore anything I post between Friday night and Tuesday morning.

Jonathan
 
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