voltage across battery when charging ?

[GhettoPop]

my PA performance 130Amp alternator charges my stock stang at about 14.5V at 750rpm idle with no accessories on. with just say the lights on, it will charge at around the low 13's at idle. these numbers are not across the battery but from my autometer gauge reading from my ignition switch as i wanted to get a "real feel" of what voltage the accessories are getting. any time up raise the rpm's to 1000 or more, it will always charge at 14V or over. keep in mind that this is using a march 1000 underdrive pulley kit which includes a smaller (i believe) alternator pulley.

if it matters i upgraded to the cable running from the starter selenoid (sp?) to the alternator with the "premium" one that PaPerformance seels with the inline 200A fuse. i believe that is a 4 gauge cable. i also replaced my old positive and negative wires from the battery as well as the cable running from the starter selenoid to the starter with PaPerformance 4 gauge cables.

in your situation, what RPM are you idling at? what happens when you bump to 1000rpm? 1500rpm? post your stats.

if that cable going to the battery is really long you may want to upgrade to a larger size to be on the safe side and it can't hurt anything. you can always try shortening it if possible.

you may also want to condier changing the pulley on the alternator to a larger diameter model such as the stock size (i think it's larger than the pa performance pulley) and some manufacturers make pulleys larger than stock.

[mpj76]

I once had a very old style (1970's) 130 amp alternator with an external voltage regulator. During my heater core swap job, I drove the car without the instrument cluster connected for about 2 days. Turns out that the alternator was excited by a charge on the same ciricuit as the cluster. Without this circuit closed, I had to blip the throttle to about 4-5000 RPMS to manually excite the alternator. I could also excite it by running a lead from the + battery terminal and touching one of the terminals on the regulator. If you're running an adequate gauge of wire and have good connections, you may have a similar problem.