i've heard that a aftermarket alternator voids the factory warranty...if this isn't correct (plmk) then forget the question:

is their any way to get 14.4v to amp w/o a new alternator?

my amp (alpine mrv-f450) puts out 80w (RMS) to each of my front speakers, and 150w to my sub (well it will monday) at 12v. our factory alt. puts out 12.7, so that means i'm getting 84.6w and 158.75w, right?

i would really like to get the 120w and 200w that the amp is capable of. especially since next month i will be getting diamond hex 6.5s for the front, and their RMS is 150w!


so would 84.6w to each diamond be enough? i don't want to lose sound quality.

could i bridge the 150w channel and one of the 40w channels? hell, that would put 190 to the front speakers.

thanx.

 

Output and input are not neccessarily proportional. In fact, generally the unit is designed for a specific input and varying that is not good for it.

With the alternator running, you should be a getting more than 12.7 volts. It should be well above 13 volts, perhaps well into 14 volts (the standard is 13.8v). If you are only getting 12.7 volts, you have one of two problems:

1. Your wiring is and connections from the battery to the amp are insufficiant. The result is a high resistance causing a drop in voltage. Your losing a few volts to heat. Make sure the wire is of appropriate size and all your connectors are real ones, not those stupid scotch-lock things. If you have it grounded at the battery, it needs to be the same gauge as the positive. If you have it grounded to the chassis somewhere else, it needs to be the same gauge AND it needs to be bonded to unpainted metal with a real ring terminal (not wraping the wire around the screw).

2. Your alternator is toast. If your meter the alternator output at the battery while the truck is running, it should show no less than 13.8 volts. Have it tested and NAPA or something and they can tell you if it is shot or not.

 

thanx. in that case i was told wrong, who'd a thunk it, by an audio place guy. i went to advance auto parts, and it was putting out around 14.2v. he said his machine was wacky lately, so i'll try at autozone sometime today too.

 

Your alternator will adjust its output voltage depending on the load on the electrical system. I've seen mine as high as 16 volts and as low as 14 volts. As for your amp, you are correct. You will get more power out of it if you run at 14 volts. The amp is rated at 12 volts because that is the standard. Basically the power rating they give you is what you should get just running off of the battery.

 

As for the speakers, the 80rms should be perfect.


Also, nobody answered if an aftermarket alt. voids the warranty, I would like to know.

I just looked up the amp, i'm not sure how exactly it is able to bridge.
I figure that you can get 120 watts RMS x 2 (at 2 ohms) + 200 watts RMS x 1(at 4ohms) in bridged mode according to the specs; which will give you 60rms per front speaker, and 200 for the sub. Sounds pretty good.

 

well if you had electrical problems that would certainly give Ford a leg to stand on to deny coverage on items effected by drops or spikes in power
would it void the warranty on your muffler, no - on your trucks computer, maybe