Big 3 upgrade major issues...

[FultonD33]

I installed the big 3 upgrade on my avy a couple days ago and its just been sitting for a few days and when I went to go somewhere my doors wouldn?t even unlock, wouldn?t crank not even a light would come on. I tested my battery voltage and I somehow had 2.58 volts    well I quickly undid all wires from my upgrade and put it on a slow charger and got it back up to cranking capacity and ran it for a while and everything works fine. What could have caused this?

 

[Loggie]

Whats the big 3 upgrades 

 

[MS03 2500]

A big 3 upgrade is a upgrade to the wiring when you install a large alternator for aftermarket amps..

But what we need is what wires did he upgrade

 

[Loggie]

I never changed the main wiring when i upgraded my alt. However, I did add additional wiring when i ran a second battery and my 1600 watt amp ran to the 2nd battery.

https://www.chevyavalanchefanclub.com/cafcna/index.php?topic=31816.0

the relay that keeps the two from canceling each other out when the car is off

Dual battery system... this sound right?

 

[FultonD33]

It could be the fact that I did not upgrade the alternator as well... as far as I know it?s still the stock alternator.

 

[MS03 2500]

A cheap upgrade is to change the alternator to a 145 amp, stock ones are only 105. You'll have to replace the belt also because the 145 is bigger.

 

[Loggie]

A cheap upgrade is to change the alternator to a 145 amp, stock ones are only 105. You'll have to replace the belt also because the 145 is bigger.

Yeah i took the that time to get the overdrive pulley

Here is a pic of the 105 vs 145 alternator