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Thanks Joel. I may not be asking the question the right way. Let me try again.
Using a vacuum temperature switch means no vacuum advance until the engine is up to operating temperature but, what is the effect of connecting to ported vs unported vacuum for vacuum advance?
? if unported, vacuum advance will follow RPM?
?ported, vacuum advance will be zero at idle and then follow RPM?
1980 L82 (5069 made), Dark Green Metalic (844 made)
Gymkhana Suspension, AM/FM/CB, Sporting a ZZ383.........
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"What we have here.....is failure to communicate..." 
Unported vac. will give the dist. full vac.=full advance all the time, except in heavy throttle, where the amount of vac. drops off.
Ported vac. will indeed be "0" vac. advance at idle, and then kick in as the throttle is opened, and the rpms will rise with the throttle opening,
Ported would be the recommended way to do it on a street-driven, basically stock engine.
Unported vac. will give the dist. full vac.=full advance all the time, except in heavy throttle, where the amount of vac. drops off.
Ported vac. will indeed be "0" vac. advance at idle, and then kick in as the throttle is opened, and the rpms will rise with the throttle opening,
Ported would be the recommended way to do it on a street-driven, basically stock engine.
Joel Adams
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Got it........ thanks.
1980 L82 (5069 made), Dark Green Metalic (844 made)
Gymkhana Suspension, AM/FM/CB, Sporting a ZZ383.........
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in Forum: C3 Engines, Driveline and Handling
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