Engine rpm

Discussion in 'Drag Racing' started by Gene Fiore, Apr 29, 2012.

  1. Gene Fiore

    Gene Fiore Member

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    On another thread I believe on this forum someone made mention that when racing with an auto trans that the amount of engine rpm drop when shifting was in indication of something...but for the life of me I can't remember what that was and can't find the thread. Anyone care to offer an opinion?
     
  2. Joe Dirt

    Joe Dirt BBF life

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    Converter slippage
     
  3. Gene Fiore

    Gene Fiore Member

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    Great...how does someone use this knowledge to evaluate their comverter?
     
  4. Joe Dirt

    Joe Dirt BBF life

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    You will want to do a wot pull and record the rpm drop on shifts (best you can) a typical 3 speed auto will drop 900rpm or more on a wot upshift. Once this is determined youn determine if it is a trouble area and there is a couple ways to tighten a loose converter if needed
     
  5. Gene Fiore

    Gene Fiore Member

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    Ok, well I went to the track over the weekend and noticed about a 1000 rpm drop in rpm when shifting. I currently have a 2800 adv stall converter. I would imagine for more performance I would not want that much of an rpm drop. Does that mean I need more converter?
     
  6. Joe Dirt

    Joe Dirt BBF life

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    Sounds like your converter is working properly big power cars with "cheap" converters can see as little as a couple hundred and it eats up power. Less drop= slippage and slower et


    On your 6 cyl i would think it would like something in the 3200 true stall range depending on how hot it is and how hard you turn it. And would probly like a 4.10+ gear it would probly pick up quite a bit
     
  7. mavman

    mavman Member

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    It means nothing unless the "drop back" rpm is more than what it was when the converter was new. Then you'd be looking at a sprag or broken stator..or worse (plum wore out...LOL)

    Converters can be built specifically to drop back 100 RPM or 2000 RPM; Depending on the application. Thats where you start to get into cheapie off-the-shelf converters and a custom converters.
     

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