Alexander Bilan wrote in a message to Bruce Legrande:
 AB> Your run of the mill GM 10SI unit charges at aprox 1200rpm.
 AB> AC Delco parts sells an alternator which is designed for low rpm
 AB> use, its output starts at about 1000 rpm.
 AB> You won't find anything that puts out anything substantial below
 AB> 1000rpm. 
Hey Alex...  I just got to thinking (surprizing - huh !? :)
When you mention the 1000-1200 RPM values above, are you talking about
the speed that the alt' needs to spin at, or are you talking about
the engine speed ?  If the crank pulley is 15cm and the alt' pulley
is 7cm, this is a ratio of over 2:1.  If the engine is at 700 RPM,
would the alt' be going fast enough to reach that 1000-1200 point
at idle ?  If not, could the sizes of the pulleys be changed in
order to obtain this rate ?
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