Hey, Charlie B! One kind-of GENERAL rule on carburetors was that you screw in the jet until you notice rpms dropping, and back out a quarter to half turn. Idle jets can be done at idle, main jets at 2 grand or so...
Of course, that may have been idle jets only. I didn't do driveability work at the dealership, and later on it was all computerized...
Maybe someone will jump in here and rightfully straighten me out on that.
Of course, if you screw the jet in all the way, and the car still runs: rebuild the carb!
