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Old 08-31-2023, 10:00 AM
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Stan Weiss Stan Weiss is offline
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Originally Posted by PAUL K View Post
The factory offset the wrist pin to make the engine run more quiet, it prevents noise from piston slap. Power can be found by installing the pistons so the offset is on the opposite side, now the piston will make more noise but will descend down the bore easier. If you install a piston with positive offset, bring it to TDC and push down on the piston top the crank will spin counterclockwise. If you do the same with a piston that has negative offset the crank will turn clockwise. If you do the same with a piston that has no offset the crank won't turn at all. Not sure how to rate this as to "how big" of a speed secret it is. I guess it's like most secrets. Once you know a secret they are either too good to keep, or not worth keeping.... I'm guessing most folks reading this thread weren't aware of why the factory pistons are offset or if they had any offset at all. But at the end of the day, as mentioned previously the most likely reason one piston was installed opposite of the other seven is human error.
When there is no pin offset the piston and the rod journal are ATDC together. Depending on the direction of the pin offset the piston will either be before or after its TDC when the rod journal is ATDC.

Stan

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  #2  
Old 08-31-2023, 10:08 AM
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PAUL K PAUL K is offline
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Originally Posted by Stan Weiss View Post
When there is no pin offset the piston and the rod journal are ATDC together. Depending on the direction of the pin offset the piston will either be before or after its TDC when the rod journal is ATDC.

Stan

Hi Stan, that's probably a better way of saying it, technically

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