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Discussion Starter #1
I am working with this ???????? in another forum.

They are stating sweped volume of the piston at a given amount of stroke will change if the wrist pin is ofset. What are your thoughts?
 

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I am working with this ???????? in another forum.

They are stating sweped volume of the piston at a given amount of stroke will change if the wrist pin is ofset. What are your thoughts?
If the stroke does not change then how could it change the swept volume? Am I missing something here? What is their argument?
 

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If the stroke does not change then how could it change the swept volume? Am I missing something here? What is their argument?

x2


Depending on the design of the engine (i.e. I can see this is a V-configured engine), having the pin offset could effect how far vertically the piston travels away from the centerline of the crankshaft - relative to a centered wrist pin piston - but overall swept volume would not change.

Example: pistons with the pins offset inboard (towards the center of the engine when installed, if you will) in a V-configured engine would potentially keep the pistons at a greater distance from the crankshaft centerline during the entire length of their sweep/stroke - relative to a centered pin piston - but they're still going to travel the same distance vertically regardless of pin location. If the arm on the crank throws them 4", they're going 4" up and down, regardless of pin location.
 

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Discussion Starter #4
I found some interesting stuff. Years ago doing some engineering work order I spent some time fooling with it. Have also in the past 67 or sos swapped piston in mopars bank to bank. I produced more power changing the ofset.

This freed up forces against rotation. But other things changed to suchas TDC. Cam changes helped too.


Check this out

http://www.epi-eng.com/piston_engine_technology/piston_motion_basics.htm


http://homepages.cae.wisc.edu/~hessel/faqs/kiva4faqs/zpistnCalculationWAndWOWristpinOffset.html
 
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