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Discussion Starter #1
Where are our cars most happy 13.9? My cars sitting at anywhere from 13.3 13.4 13.5 13.6 with the system off or on 1/0 gauge to 4 gauge and a spare battery in the trunk...
 

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Where are our cars most happy 13.9? My cars sitting at anywhere from 13.3 13.4 13.5 13.6 with the system off or on 1/0 gauge to 4 gauge and a spare battery in the trunk...
That's completely normal. The reason it's not putting out the higher voltage is because the computer is telling it not to, since it thinks it doesn't need it. I have a 2011 and it's the exact same as your 2010 pretty much, and I sit at around 13.8V even with my 270A alternator I have in. It's no big problem to not be sitting at the 14.4V mark, because even with a high powered system, that isn't really losing that much power output from your alternator.

Don't worry about it, there's nothing you can do unless you look into an MLA module to basically bypass the computer and have your alternator put out the charge you want all the time.

If I have my system on for long periods of time, I notice that it will maintain a higher voltage. Either way, my voltage doesn't even drop to 13.6 when starting at 13.8 with 2400 watts RMS.

Where are you measuring it at also, because if you measure at your back battery, then depending on how good your grounds are, you are probably losing a little voltage(like .5V or something). If you measure it at the positive stud on the alternator and it reads 13.4V, then maybe you do have a problem, but it could also be normal because the weather plays a role in your voltage, as does if your headlights are on, fog lights, A/C, etc.
 

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Discussion Starter #4
how do you put in a happy knob also how hard was it to swap out your alternator? from the bottom right? and have you done the big 3 yet where did you run your grounds too on the subframe? I need a place that's out of the way of moving parts.
 

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Discussion Starter #5
oh hey ben I'm running a mmats 3500 at 2 ohms grounded on the seatbelt bolt on the driver side with both amps mounted to the back of the seat I also have a jbl 100x4 and a oversized jbl 12 gti. And also is it even possible that you can run a happy knob on an 08-11?
 

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When I did my ground upgrade , the grounding kit that I bought has several different lengths made up and I just used the length that was closest to matching the factory wire and just put them in the same spots as the factory grounds .
 

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Discussion Starter #7
I cant tell where the alternator is ground at thought i was under there and boy is it tight and I'll be using all 1/0 gauge...ya dont think i'm staying with one 12 do ya? LMAO :)
 

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I'm running between 14.2-14.4. Verified with DOM and scantool.
 

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how do you put in a happy knob also how hard was it to swap out your alternator? from the bottom right? and have you done the big 3 yet where did you run your grounds too on the subframe? I need a place that's out of the way of moving parts.
I'm not sure what you mean by a happy knob, unless you are refering to the thing that sort of acts as your PCM...and i have no clue about that.

But yes, the alternator was a real pain. It took about an hour to finally figure out what to remove to get it off. We had to jack the car up with the car lift, and then there is a black plastic peice that just unbolts to view it from below, then the bolts for like the axle I think it is, they are real huge bolts and if you mess it up your alignment will be off. We had to remove those to drop it down far enough to even be able to fit the alternator out, we tried every angle. And also the alternator has a black plastic housing around it for the cooling, which has to be completely removed off of it to be able to fit it out, and that was really hard as well. And most likely if you get a good high output alternator the casing won't fit back on it, so you can't have it on there with the new one.

All-in-all, if you can afford to have a shop do it, then definately have them do it. It was a real pain in the ass for me and my moms boyfriend who owns a car repair place and has done this stuff for over 20 years. He told me if something happens and my new alternator fails and has to be removed that he's not touching it, because it was too big of a hassle lol, unless I pay him of course.

And yeah I have the big 3 done in all 1/0 gauge wire. The alternator has it's positive wire that leads to your fuse box, and then another wire from there to the battery. And the two grounds are from the engine in the front middle-right to the battery negative, and then one from the battery negative to right beside it, on a weld point.

I left all the stock wires in place as well as all my 1/0 wire. My power wire for the alternator is wrapped in the plastic loom and wire tied to the existing wire. Same with the negative wires. Remember to leave a little slack to allow for movement of the engine and such.
 

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Discussion Starter #11
in the car audio world some people refer to the knob that controls your alternator output as a "happy knob"i know weird LOL.
 

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Discussion Starter #12
yes I know and I will :) and yes I know about the black plastic cooling shroud so I would be running the positive from the back of the alternator to the battery not to the fuse box correct? I know that on the newer style silverado's you run it to the red fuse box by the battery.
 

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Discussion Starter #15
I defiently gotta get one!! but hey do you know how it would work with a stock 4grove alternator? I was watching a video on youtube and they where talking about a huge voltage jump.....nothing to detramental thought.
 

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yes I know and I will :) and yes I know about the black plastic cooling shroud so I would be running the positive from the back of the alternator to the battery not to the fuse box correct? I know that on the newer style silverado's you run it to the red fuse box by the battery.
I kept the stock in place to the fuse box, but ran my 0 gauge wire straight to the battery.
 

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ok because the MLA looks pretty bad ass and from what I've seen on the youtube video wow they see a huge voltage jump :)
Yeah they keep your alternator running at the higher voltage for the purpose of your amps and stuff...let me know if you find one for the 2008-2011 focus and how much
 
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