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Re: Speedo Drive Ratios

To: Jeremy Fergusson <ferguss@philly.infi.net>
Subject: Re: Speedo Drive Ratios
From: Mike Causer <mikec@dial.drakken.com>
Date: Tue, 04 May 1999 20:01:31 +0100
Jeremy Fergusson wrote:

> I've recently changed the diff ratio in my Seven from 4.11 to 3.89. Now
> I need to make the speedo read correctly.
> The nylon speedometer drive gear for the 4.11 is blue with 25 teeth. If
> I go the other way, a drive for a 4.55 dif is white with 22 teeth. What
> do I need for correct reading with a 3.89 dif and where can I find one?

Easy!   Now where's m'slide rule?   Ah yes -- 25 times 4.11 divided by 3.89
-- that's 26.4   There you go, find a drive gear with 26.4 teeth.


Oh, BTW,  I used my 1968 sliderule; possibly the '63 would have given a 
different answer, being contemporary with the 105E.



No charge for this advice.....

Mike


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