HO Alternator?

GenY

CarAudio.com Recruit
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5
USA
I was wondering if I should upgrade my alternator to something bigger? My headlights dim a tiny bit but nothing serious. I currently have a 150A alternator in a 2012 Ford Focus SE 4 Cylinder. I'm currently running about 1300 in combined wattage from all aftermarket equipment - receiver, door speakers, sub, amp. My sub is running at 1 - Ohm on a Mono MTX Thunder 1000.1 and my door speakers are running at 4 - Ohm into a Apline KTP-445-U dash amp. My amp's power wire is 4g Memphis wire that is connected to a XS Power D4700.
I believe both amps are both class D just not sure the precise efficiency. Thank for any input. Cheers.
 
Have you done the Big 3 yet? If not I would try that with some ofc 1/0 quality wire or welding wire first before doing the HO Alternator. I ran almost 2k in wattage on a 130 amp in my ford explorer with the Big 3 and had no issues. Just make sure you get good quality wire and that it is ofc or the welding wire. Do it from the battery back to your distribution blocks and for your grounds as well.
 
First I'd follow what @Coolhand20th said.
H.O. alternators are expensive and probably not necessary for your size system.
If you still have dimming after a big 3, this is the rare circumstance that a capacitor could actually help. it can at least take the edge off the headlight dim.
 
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Ditto with what Coolhand20th and Deon1818 recommend. Especially, if you're running 2 class D amps. The Big 3 will definitely help your electrical. If your headlights are still dimming, then you should consider the H.O. alternator. Make sure the Big 3 is 1/0 AWG OFC wire.
 
I use welding wire with good success as do many others here and at DIYMA. The Execelene is great flexible stuff and well over 1K in strands. It has gone up in price and I kick myself for not buying more when it was 65 bucks shipped for 30 feet of it.
 
If you have the halogen headlights you will get dimming even with very slight voltage dips. Halogen lights are pretty sensitive to voltage drop. I have a 16 focus running around double that power and drop to 12.5 idle with stock alt, big three, and a baby northstar battery. I do have the adaptive hid headlights though. Break out a multimeter and see what your voltage is dropping to.
 
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GenY

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