Vance---As previously stated in an earlier post, I can't go to my car
and try duplicating the action of the thermostatic vacuum switch, so I
will ask again for clarification. Please bear with me.
On the '73 and others there is a "fast idle" setting accomplished by
adjusting the Choke cam linkage. This will give an idle speed increase
up to about 1300 rpm with the engine either cold, warmed up, or in
between. If I were to push in the Choke knob, the engine speed would
return to normal idle, even before fully warmed up.
What you are saying is that in your setup, the thermostatic switch would
keep the timing advanced throughout the warmup time, even with the Choke
influence on the fast idle circuit out of the picture. Your engine would
continue to idle at speeds of about 1300 rpm. Only when the coolant temp
came up to "normal" would the idle speed drop. True?
Dick
Vance wrote, in part.....
.....The thermal vacuum switch opens when the engine is fully warmed,
and retards the timing by 14-16 degrees to reduce emissions at idle....
This also means that your "fast idle" function on a cold engine is
dependant on the vacuum retard being disabled, and that being able to
obtain the correct "slow idle" speed when the engine is warmed up
depends on the vacuum retard being enabled.
Disabling the vacuum
retard will make it more difficult to obtain
the correct fast/slow idle function during the warm-up of the motor.
Cheers,
Vance
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