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Under the static power pull at 4,250 rpm, the Lambda meter shows12.8:1 air/fuel ratio, while pulling 503 lb-ft of torque, uncorrected.This mixture reading is considered "safe"--a ratio at which a dyno pullthrough the rpm range can be made. Had the static pull showed a verylean ratio, the carb would be jetted for more fuel to avoid a leancondition that can quickly melt pistons. Next, the engine was runthrough a series of sweeps at 300 rpm/sec, starting with short sweeps,checking the air/fuel ratio, and then repeating the procedure withlonger sweeps until the sweep covers a full pull over the operatingrange of the engine. Brule studied the data from the instrument readingsof the Lambda meter, in conjunction with the dyno's calculation ofair/fuel ratio based on measured fuel and airflow, and the engine'sbrake specific fuel consumption. Looking at these numbers, it wasdetermined that the mixture was a little too rich for peak power.