Might try checking your TVS (Temperature Vacuum Switch) on your thermostat
housing.
When the car gets hot or almost overheating,( with my Buick engine its about 220
degrees) the switch applies manifold vacuum to the distributor, instead of
ported
vacuum, thus advancing the distributor at idle. An advanced engine at idle has
better
cooling properties, it also idles faster. If the switch is defective and
opening too
soon it could do that. But since your engine is pinging up hills when you get
warm,
are you sure that your not getting too hot? Is your gauge working properly? You
can
bypass the switch and hook up the dist. to the carb and plugging the manifold
fitting.
Just my 2 cents worth, can't hurt to look.
Kyle Hagemann wrote:
> At 06:37 PM 1/24/99 -0600, we got some some E-mail from snyler.
> > My 70 1600 is tuned and carbs balanced, but it ain't perfect. On a
> >trip out to the grocery store (7 mi) the car runs beautifully,but on the
> >trip back I notice some pinging on hills. Idle speed also changes from
> >just under 1k rpm when cool to about 1500 when well warmed up. Is this a
> >vacuum thing? do I have a crack opening up (or closing) as the engine
> >reaches operating temperature?
> > I retareded the timing a bit more and with octane boost the ping is
> >gone, but the idle change still happens.
> > Still, it's running well enough to meet up with folks interested in
> >a Hill Country run :)
--
Scott Hilmoe
"clockmkr"
'67 - SPL311-07317
'67.5 - SPL311-012752
'68 - SRL311-04294 (I finally got a 2000! Now to get it roadworthy.)
"They that will sacrifice liberty in exchange for temporary
safety deserve neither liberty nor safety." Ben.Franklin
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