[another69camaro]

just taking new car out on the street for a few small test drives before bring it to the track.finding the batt loosing charge pretty fast down from 100% to 70% after about 3 or 4 miles.it has a new deka agm batt and a east coast 120 amp super mini with a 5 inch pulley on the crank.it had a #8 wire going back to the batt switch from the alt.so just to try i put a #6 wire from the alt right to the batt stud on the starter so its a shorter run with large wire and its doing the same thing.car has a pro star 500 pump,msd 7531,eletric fan/meizzer water pump/eletric shifter etc.checked the volts at the back of the alt 13.5 @idle and 14.5 @ a little over 2000rpms.the batt is ground to the frame under the batt tray not sure if that would affect the charging running out of ideas.could it be just the low rpms on the street just isnt enough to keep up.thinking about a bigger crank pulley if there even made bigger than 5 inch for a moroso keyed drive mandrel.any ideas thanks?.sean

 

[RRRAAAYYY2]

If you have 13.5 at idle, with everything on, you should be good to go. I would pull the battery and have it tested.

 

[another69camaro]

it had a new yellow top and was doing the same thing so i just put the new deka in after reading about the troubles with yellow tops and same thing with the deka.i doubt its both.thinking since this thing has such tall gearing and tires with a glide its going down the road at such a low rpm like 1500 that its just not enough amp charge to run all this stuff.

 

[RRRAAAYYY2]

Something is up, the battery shouldnt be losing 30% of its charge in 4 miles. It is designed to give you at least 30 miles with no alternator at all. So you are either pulling huge amounts of power from it, or is the reading wrong? (Could be a bad reading, or not 100% accurate) Techinally though, it shouldnt drop at all if you have an alternator on it. Especially if you are reading 13.5 volts at idle, as that is more than required so there should be no draw on the battery. (13.8 is over working an alternator, but anything above 13.2 is alternator produced/supplied) So if you are going to idle a lot, you need to change pulleys to get the alternator spinning faster.

 

[another69camaro]

found it.i screwed up when i put the #6 from the alt to the starter stud.the main batt cable comes to a ford regulator and then out of the reg to the starter.i guess you cant charge back through the regulator from the starter stud.i put the alt wire on the batt cable side of the regulator and its charging good now.

 

[RRRAAAYYY2]

Cool, I like easy fixes. Hope it didnt take too long to figure out.