Rep Power: 512

I took a leisurely drive yesterday, and on a long downhill portion of my drive and a bit of spirited driving, I notice my voltage was at 12.5V. I get off the gas, and the voltage builds back up to 14.4V. So, I busted the phone out to take some video
http://www.youtube.com/watch?v=HolYJWxdvuQ

A/C was turned off, head unit turned off, and with amp remote coming from the h/u, the amps were off, too.

Video starts out looking @ my speedometer, cruising at just over 55mph, RPMs sitting at about 2250, then down to my VAFC-II (only used for monitoring, now).
Notice the RPMs match, and throttle position is 0.00%. I step on the gas to ~20% throttle, voltage drops to 12.6V, release throttle, voltage builds back up to 14.4V, then I do it again for redundancy's sake.

I did the "test" again on flat ground, and it voltage only dropped to maybe 13.7V. This is the first time I've really noticed that happen.. Just wondering if that's normal or if it's a sign that my alternator's starting to go..

 
Rep Power: 812

its normal, the ELD plays with voltage all the time. i had a voltmeter and noticed the same thing. if your voltage is low around 12v, turning on accessories (a/c or fan blower, etc) should make the voltage go back up. its mainly to cut alternator power when its not needed.

 
Rep Power: 512

Cool, thanks. I'm just not used to seeing the voltage drop below 13.7