Jon Larsen wrote:
> Extra credit: The spark plug contacts in the cap are indexed
> to the rest of the mechanism so that the rotor is in closed
> contact with a spark plug when the coil 'fires'. The only way
> for it to be out of registry is if the distributor shaft is
> twisted or something. Rotating this whole mess a few degrees
> one way or the other changes when all this happens in relation
> to the position of the pistons in the engine (timing and advance).
Extra info for this point...
The rotor end and distributor cap contact are both fairly
wide, a half inch or so.
Because of this, the rotor and cap contacts are "pretty darn
close" for 30 or 40 degrees or more of distributor turn.
Because the distributor turns at half speed, this becomes
60 or 80 degrees of timing that is "close enough".
In other words, the rotor and cap should be lined up well
enough for almost all timing situations. There is no tight
tolerance where a couple of degrees off and it won't
work.
--
Trevor Boicey
Ottawa, Canada
tboicey@brit.ca
http://www.brit.ca/~tboicey/
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