Speedo Recalibration Help
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Instructor
Joined: Aug 2006
Posts: 134
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From: Apple Valley MN
Speedo Recalibration Help
I need a little help with this Speedo Recalibration. Considering this formula =
(RPM * Tire Dia) / (Diff Ration * Trans Ratio * 336) = MPH
My 81 had the Performance Axel – 2.87:
(2000 * 27.1) / (2.87 * 1 * 336) = 56.2 MPH
New Diff = 3.31
(2300 * 27.1) / (3.31 * 1 * 336) = 56.0 MPH
How many teeth do I need to go up? Any idea what was stock?
Thanks in advance.
(RPM * Tire Dia) / (Diff Ration * Trans Ratio * 336) = MPH
My 81 had the Performance Axel – 2.87:
(2000 * 27.1) / (2.87 * 1 * 336) = 56.2 MPH
New Diff = 3.31
(2300 * 27.1) / (3.31 * 1 * 336) = 56.0 MPH
How many teeth do I need to go up? Any idea what was stock?
Thanks in advance.
Last edited by MN81C3; Sep 19, 2007 at 12:33 PM.
