Pi * Diameter = Circumference. You want the ratio of the two pulleys.
(5.5 * Pi) / (2.5 * Pi) = 5.5 / 2.5 = 2.2 Then at a particular RPM (lets
say 1100 rpm) you should be rotating the alternator at 2200 rpm.
TonyC
-----Original Message-----
From: Henry Delchi <hddakota1993@yahoo.com>
To: dakota-truck@dakota-truck.net <dakota-truck@dakota-truck.net>
Date: Monday, May 31, 2004 10:24 PM
Subject: DML: Pulley Size- Mathematical Question
>
>Hello all,
>
>I have a mathematical question for the mathematicians
>(or someone just good at math)
>
>If a 5.5" crank pulley is turning at 1100 RPM's, how
>many RPM's would the 2.5" alternator pulley be
>turning?
>
>What diameter would the alternator pulley have to be
>to keep it spinning at the same speed figured above
>but with a reduced crank pulley speed of 700 RPM's?
>
>Please also provide the formula used to figure this
>out.
>
>Thanks!
>Henry Davis
>
>
>
>
>
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This archive was generated by hypermail 2b29 : Thu Jul 01 2004 - 00:15:16 EDT