Re: Dual point dist

[Jerry in Houston <glewis4457@xxxxxxxxx>]

It is my understanding that the second set of points
is used only during engine startup and not once the
car has started, hence the vacuum switch, but it was
indeed to reduce emissions during engine start.

Jerry in Houston

<<From: Jon Pike <jhpike@domain.elided>
Subject: Dual point dist

> I was dismantling the engine from my 71 spider and
> noticed that it had a dual point dist.  Can anyone
> tell me the specs on this?  It is a magneti-marelli
> dist.  Two sets of straight points.
> 
> Thanks
> Kelly

Not sure if it would be the same model on your 71,  
but our 77 has a 
dual point Marelli as well.

What they do with it on our car, is set the second set

of points with a 
different gap, and there's a vaccum switch that shifts

between points 
with low or high manifold pressure.  Reason for that, 
is a slight 
retarding of timing and therby better smog results 
at(?)higher vaccumm 
conditions.  Or, maybe the other way around.>>
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