In need of remembering prop number conversions.

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • gearhd48
    Senior Member
    • May 2015
    • 139

    #1

    In need of remembering prop number conversions.

    After 5 yrs of being away I have forgotten how to convert prop numbers. Example: an Octura M 442 compared to the OSE 4214250 42mm or 1.65 with the 2.32 pitch. This getting old thing sucks when you can't remember! LOL
    SW26 V3 Green 35mph , Swifter Hydro 26. Delta Force 35. cars ,3 Rustlers 45-76 Mph.
  • fweasel
    master of some
    • Jul 2016
    • 4281

    #2
    The octura 3 number props are (pitch ratio in inches)(blade diameter in mm). So the 442 has a 1.4 pitch ratio and is 42mm in diameter. The OSE prop you mentions is 42mm in diameter, 1.4" pitch ratio.
    Vac-U-Tug Jr (13mph)

    Comment

    • gearhd48
      Senior Member
      • May 2015
      • 139

      #3
      I thank you for the reply, but how is the total pitch calculated? also how did you get the pitch ratio out of the total pitch ratio? I know there's a mathematical way of finding this, which is what I need to relearn. Thanks
      SW26 V3 Green 35mph , Swifter Hydro 26. Delta Force 35. cars ,3 Rustlers 45-76 Mph.

      Comment

      • TRUCKPULL
        Fast Electric Addict!
        • Apr 2007
        • 2971

        #4
        42mm in diameter, 1.4" Average pitch ratio.

        42mm X 1.4 = 58.8mm per. RPM

        LJ
        Past NAMBA- P Mono -1 Mile Race Record holder
        Past NAMBA- P Sport -1 Mile Race Record holder
        Bump & Grind Racing Props -We Like Em Smooth & Wet

        Comment

        • gearhd48
          Senior Member
          • May 2015
          • 139

          #5
          Thank you Truckpull! Now the two props I gave as an example are apparently both 1.4 pitch x 42mm, but according to specs the OSE one it has a TOTAL pitch of 2.32 ,and the Octura has a 2.64 TOTAL pitch. I'm sure this should have a performance difference right? I'm dangerously assuming the slight difference is that the 2.64 total pitch might be a little more aggressive. Right? How do they get the TOTAL pitch numbers?
          SW26 V3 Green 35mph , Swifter Hydro 26. Delta Force 35. cars ,3 Rustlers 45-76 Mph.

          Comment

          • TRUCKPULL
            Fast Electric Addict!
            • Apr 2007
            • 2971

            #6
            1.4 pitch x 42mm, Octura has a 2.64 TOTAL pitch. Sorry but the 2.64 TOTAL pitch is on a 642 prop = 42mm Dia. and a 1.6 pitch NOT a 1.4 pitch prop.

            Diameter: 1.65" (42mm)
            Total Pitch: 1.4x1.65=2.310"

            LJ
            Past NAMBA- P Mono -1 Mile Race Record holder
            Past NAMBA- P Sport -1 Mile Race Record holder
            Bump & Grind Racing Props -We Like Em Smooth & Wet

            Comment

            • gearhd48
              Senior Member
              • May 2015
              • 139

              #7
              Thank you sir that is what I needed! My mistake on the 2.64.
              SW26 V3 Green 35mph , Swifter Hydro 26. Delta Force 35. cars ,3 Rustlers 45-76 Mph.

              Comment

              Working...