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  • Fly wheels

    Is it better to leave the flywheel stock and balance or have it lightened up and balanced?

  • #2
    I have access to a large lathe so it's easy for me to turn a few lbs off mine. Reasons for doing it; 1) the engine spools up faster. 2) less weight on the rear main. The weight is taken off the OD, not the center making the mass less effective. All engine manufacturers have been lightening their flywheels. The stock FW weighs about 63lbs. Show me one auto manufacturer whose FW weighs anything near that! Crappy roads made the heavy FWs necessary, better roads has allowed much lighter FWs to be used. Reasons for not doing it, It isn't stock. Your engine may have slightly different running characteristics. I generally take them down to about to 57-55 lbs, not much difference! Some people take them to down thirty lbs. Then have it properly balanced . I find it to be a desirable modification.


    • Denis4x4
      Denis4x4 commented
      Editing a comment
      I have the welded counter weights in the '31 with a 39 pound flywheel. In an earlier post I mentioned that the 3:27 gears didn't work. Perhaps this is why!!!

  • #3
    Generally, Henry used the heavy FW because his crank was not counterweighted.
    Once any of us went to a counterweighted crank, the need for such a monster of a FW was negated, and most of use then use a FW that has been lightened


    • #4
      I run my unrestored tudor off road and it just keeps chugging places that my V6 pickup won't go, it really is amazing how it runs on the
      old rough farm roads. Maybe the FW helps?


      • #5
        leave it stock,if you counterbalance run the B weight,10 pounds less than an A..the weight makes the driveability..


        • #6
          a lighter FW is gonna help not beat up the mains as much.........


          • #7
            Thanks for the info. That was a question that has lingered in my little brain for some time.


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