Sounds like the voltage is right where it should be. A 12 volt system should charge at 14.8 volts +/-. I would be worried if it was anything other than 14.8 volts, plus or minus a tad. The voltage was taken at the battery? Did you check it with another multimeter? The voltmeter on the timing light will have an accuracy factor of a few %. I take it your car is completely stock, if so the voltage sensing wire is connected to the voltage regulator through a fusible link to the main splice. The main splice connects the red B+ wire from the alternator, the red charging wire to the battery, the volt sensing wire to the voltage regulator and the system power up wire to the horn relay. Any voltage draw downstream from the horn relay, brake lights, radio, ignition, etc. is sensed by the voltage regulator. The voltage regulator will then up the output of the alternator to keep the voltage at the main splice at 14.8 volts. The voltage regulator should have kept the voltage at the main splice at the exact same voltage with the old alternator as it is now keeping the voltage with the new alternator. Perhaps the old alternator was defective, or perhaps when changing the alternators you cleaned up some terminals to get a higher reading? Did you check the old alternator with the same volt meter equipped timing light?
