I recently raised my idle because while it was good enough in warmer temps, it was too low in cold temps to keep the engine going after I started it unless I helped it along for 30-40 seconds. I am guessing it was around 600rpm....I raised it a bit (no tach)....and its much smoother than before and idles on its own even when started at 0F....great improvement. Its a bit lower (sounds slower) than on my dad's SD...which is set to the max of 850. So maybe 750-800ish is where I have mine, and I like it at that speed.

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