Increasing rpms with AC on

93CalypsoConvert

Active Member
Nov 26, 2020
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Virginia
Is there anything I can do to increase my idle rpms while my AC is on? My idle sits between 600-700 rpm, but when the AC is on, it drops to 400-500 depending on the temperature of the engine. I feel like the thing is about to stall, and at that low of rpms my alternator barely even charges. It is carbureted, so I considered finding a 12v solenoid to push the throttle open while the AC is on to make it idle up. Anyone have and ideas to make it idle up?
 
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ECM uses the IAC to bump the idle. But being carbed, I would think the only thing to do would be increase idle. I know stock idle is usually around 800-900. Try increasing your idle and see if it helps with AC on.

I also know that 600-700 has a nice old school lope.
 
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The general is right
The carb'd a/c car would have had a stepper motor bolted to the throttle plate
These shorted out on a regular basis and I threw away several
You should be able to find one and they work well
They just got power thru the ac clutch coil circuit
 
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I used to take the stepper motors off of mid 80s cadillacs in the JY. They worked well to increase rpm. They are easy to fab to work. I'd use a relay triggered by the the low pressure switch.

Screenshot_20210919-032141_Chrome.jpg
 
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