Hey guys i've just got a new system put in my car it's a T10001bd and two 12inch p3's. I got a stringer wire kit that came with a cap 1.2 farad i also upgraded my aternator to 140amp but i still cant turn this sucker up with out my subs losing power any ideas?

 

you mean a different sub box?

 

how does changeing the box help

 

well yeah it does but as soon as a turn it up my subs lose power. I was looking at the cap it shows it drop to lik 9 volts and with my alternator i dont know why it's doing that and it's in a pretty good ported box

 

1) remove the cap
2) what gauge is the wire from battery negative to chassis?

possible problems
* bad ground on the amp
* gain settings
* faulty alternator

your alternator is rated 140A, but at what RPMs?

 

im not sure at what RPM and i payed for the install so im not 100% sure how to do everything i know all about the ground and gain with is at like 0 right now if i turn it up it sucks even more juice and the wires from my battery are all stock

 

You need to have a at least gauge 2 (recommended 0) wire running from the alternator + to the battery + terminal and 0 gauge from battery - to chassis. It is also recommended to have gauge 0 connecting the engine block with the chassis. This is called the big 3 upgrade (due to upgrade of 3 connections)

Stock electrical system is not designed to handle so much current flow for extended periods of time.

Even if this is not the reason for your issue, big 3 upgrade is still recommended.