Do you have enough power coming out of your alternator? I sure didn’t. But it took me a long time to realize that. When you have extra demands on your electrical system sometimes the stock alternator just can’t handle the load, especially at idle.

I finally figured out that I had a problem when I replaced my battery. Everything was working great for the first few days and then little issues that I’d seen before started popping up. When your alternator can’t put out enough power for your car’s electrical requirements then the battery has to act as a buffer. The end result is that your battery is perpetually depleted and your car’s performance can suffer.

I’ve got quite a few things that draw extra power: 1000 watt stereo, dual fuel pumps, upgraded ignition system, gauge cluster (w/ a wideband), etc. Sometimes people think that the battery powers the car’s electrical components and the alternator charges the battery. But in a properly functioning environment the alternator should provide the electricity a car needs (they battery is really only for starting the car and running things if the car is off). In situations where you use more power than you have there’s really only one choice- upgrade the alternator.

I went with a 300 amp SPX alternator from DC Power. The quality on this alternator is first rate. The SPX is a little bit larger than the stock alternator but fits perfectly and looks amazing. So far no issues- it runs like a champ and my car has never seemed happier.

Info from DCPower’s Website:

The Large Case DC Power300 Amp SPX series high output alternator produces 300 amps at 1800 engine RPM and 195 amps continually at low idle while capable of up to a 75% generation efficiency. The rectifier is mounted onboard the alternator and consists of 12 75 amp press fit bosch diodes. The brush holder assembly and slip ring are environmentally protected and the bearings are heavy-duty, oversized premium bearings. The alternator housings are precision-machined cast aluminum and all components are of OEM quality.

Output Voltage: 14.8
Idle Amperage: 225
Hot Idle Amperage @ 200ºF: 195
Max Amperage: 300
Hot Max Amperage @ 200ºF: 250

Posted by Cam, Feb 21, 2012