Stroke length question

Discussion in '96-04 - 2V Specific' started by ripper, Jun 27, 2007.

  1. ripper

    ripper Well-Known Member

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    Does anyone know what the stock piston stroke length is on a PI motor? My motor was bored .020 over and the cams are def not stock which we thought they were. .535/.535. Stock i think is .505. Im not complaianing but i need to know what is going on here. The guy that built my motor is on vacation and i cant get info untill he returns. I did some research and came up with a stock PI stroke of 3.552. Is that right? Mine is 3.554 :eek:. I dunno if this is because of the oversize bore or if he was adding stroke to the motor. My compression is 9.1:1. We are tunning thursday and i want to be able to know exactly whats going on.

    Sorry if i sound like a idjit here but im not even close to a mechanic LOL.
     
  2. firstonraceday

    firstonraceday Active Member

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    stock stroke on 4.6s is 3.543
     
  3. ripper

    ripper Well-Known Member

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    Hmmmmmmm now im confused as heck LOL. Does that mean i have a stroked motor?
     
  4. DropTopPony

    DropTopPony Administrator Staff Member Admin SN95 Supporter

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    no, a stroked 4.6 is more like 3.75...yours is stock
     
  5. Paul

    Paul Legend

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    Agreed. Given the very nominal difference (a few thousandths) in stroke, I would say you have a stock stroke motor. Stroker crankshafts typically have more significant differences.

    For example, a 351W uses a 3.500" stroke, but my motor has a 4.100" stroke. That, combined with an additional .040" overbore gains me an extra 71 cubic inches.
     
  6. ripper

    ripper Well-Known Member

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    Thanks guys i understand now. :thumb: