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Is a 300 amp alternator good?

A 250 or 300 ampere aftermarket high output alternator should provide enough power for all your car’s systems and your high-powered stereo too.


What is the highest output alternator?

The highest 12 volt produced by Prestolite Leece-Neville is the J-180 mount 4890JB and Pad Mount 4962PA both of which put out 320 amps. When it comes to 24 volt alternators there is one manufacturers that really stands out – C.E. Niehoff has their 500 Amp C-803D.


How many amps does a 12 volt alternator put out?

Typically a 12 volt DC unit will begin making power around 1000 rpm’s. Remember, this is alternator-not engine speed. The curve is not straight either. Generally 1200 rpm’s = 10amps, 1500rpm’s = 20 amps, and 2000rpm’s = 35 amps, max output is reached at 4500 rpm’s (51 amps).


How big alternator do I need?

Your alternator should be capable of delivering rated output equal to the maximum acceptance rate of your house battery bank. In other words, the alternator’s rating should be equal to 25 percent (lead acid) 30 percent (gel) or 45 percent (AGM) of your total battery capacity.


How do I increase alternator output?

Selecting different sized diodes can alter the output regulation of the alternator. A smaller diode will increase the charge voltage by more than a larger diode (due to the voltage drop varying with the diode current).


Is 15 volts too high for alternator?

Higher than 15 volts indicates a fault in the charging system’s voltage regulator or related circuits. If it’s substantially excessive, this can cause electrical system and/or battery damage. You mentioned your voltmeter runs at about 15 volts most of the time.

Also read:  What is the smallest alternator you can buy?


How many amps does alternator make at idle?

Most late model alternators produce 120 to 155 amps or more. Current output increases with engine speed, from around 20 to 50 amps at idle up to the unit’s maximum output at 2,500 RPM or higher (refer to a service manual for the exact charging output specifications for your vehicle).


What does adding a second battery do?

Battery #2 (which is often a deep-cycle battery) provides all power when the vehicle is off. This way, you don’t have to worry about “killing” you starter battery if you plug in a fridge, or run your winch, etc. etc.


Should I get a high output alternator?

Every 100 watts of audio needs 16 amps of power. If you use a stock alternator, your battery won’t last long because it doesn’t have the endurance to handle your audio upgrade. Installing a high-output alternator helps you support your heavy-duty system or other demanding applications to your car.


Can alternator voltage be adjusted?

If your vehicle is on the older side, your alternator may have a manual voltage adjustment on the regulator that can be changed using a screwdriver.