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      09-26-2013, 09:24 AM   #38
Boss330
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Quote:
Originally Posted by NISFAN View Post
I don't agree with your last paragraph. Bore is used as a common easy measuring yardstick, but it is actually piston area that counts. As bore is squared in the formula Pi D^2/4

This gives us piston area of 63.053 for the S55 and 55.417 for the N55. Which makes the N55 12.1% smaller in 'effective bore' vs 10.7% larger in stroke.

The weird thing is.....long strokes are FI friendly, as there is more density of Fuel/Air in the cylinder, it takes longer to burn. Also, smaller bores make detonation easier to control.
Thanks for the correction