Voltage Regulators and High Output Alternators
When you upgrade your existing alternator you shouldn't need to upgrade your voltage regulator. When upgrading to a high output alternator you rarely need to change your voltage regulator. The voltage regulator controls the alternator output by sending power to the rotor (field). The rotor spins inside of the stator, the reaction between the rotor and stator is how power is induced within the stator. The voltage regulator senses the battery voltage, if the battery needs more power the voltage regulator sends power to the rotor coil turning the alternator on. If the regulator senses that the battery or system needs a lot of power it sends maximum voltage to the rotor making it a big electro magnet thus causing the alternator to produce maximum power. If the regulator senses a small need at the battery it will send minimal power to the rotor causing the alternator to produce little power.
Never does the alternators amperage go through the voltage regulator. The area of concern when changing to a high output alternator is the amperage draw of the rotor. The voltage regulator does have a field amperage rating and because it has direct contact with the rotor you must be concerned with the amperage draw of the rotor. If the amperage draw of the rotor is greater than the rating for the voltage regulator the regulator will fail.