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Discussion Starter #1
Hey folks, first post. I'm new here, having just bought a mint '88 LX notch last summer. The car is mostly stock, only modifications done to it are a custom cat-less H-pipe exhaust setup (bought with it), 130amp alternator (installed myself) and complete sound system upgrade (also done myself).

I've been looking at installing an electric fan to replace the stock clutch fan on the Mustang. I don't have any cooling issues, but I heard it can free up a decent amount of power and is generally more efficient. I upgraded the alternator to a 3G 130amp unit to accommodate my roughly 1000-1500W (nominal load) sound system. I have two subs in the trunk hooked up to a 1000W RMS amplifier that has the gain turned down a bit, so I estimate they are probably supplied with about 600-700W from the amplifier at any given time. The speakers are also hooked up to a 200W x 4 channel amp that is also toned down a bit, so I assume is running at about 400-500W total at any given time. I also have a 2 Farad capacitor installed to level out the power draw a little.

I don't know exactly what the amperage draw is from that. I know my headlights don't dim at all at idle, but my voltage gauge seems to dip a bit on bass hits. My question is: could I run an electric fan like the Black Magic kit which has an 18amp draw without running into electrical issues on my car?

Quick edit: My battery is an Optima Red Top.
 

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At max RMS (1000 + 800), I am pretty sure your system can draw 150 amps.

Current (AMPS) = Power (WATTS) / Voltage (VOLTS).

So, AMPS = 1800 / 12.

Obviously, it doesn't draw that continuously - what size fuses do the amps have - because if those are not popping, then you know that it is not drawing more than that.

Even if your headlights are not dimming, I think that is thanks to the capacitor, not the sufficiency of the alternator or the battery necessarily. That charges very fast whenever the draw is nominal...but, your battery does not, and it is at least possible you are going to end up with a click one day when you go to start the car if you push that system too hard for too long because your battery will drain instead of charging.

I could be wrong, and I am likely being way conservative (that is, grossly over-estimating the power output of the amps), but the formula is what it is - what I would do is get a tester and determine exactly how many watts the amps are putting out, determine the actual voltage output (likely more than 12) and then you KNOW what the draw from the stereo is. :yup:
 

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Discussion Starter #3
Appreciated. Unfortunately the car is stored for the winter and I won't be going out there to test the stereo equipment anytime soon. Perhaps I'll try that in the spring.

I'm rather careful when it comes to making sure my battery has enough of a charge. I always turn down the volume completely when I enter my neighbourhood out of consideration for my neighbours, but also to give the alternator a chance to recharge the battery enough for the next start-up. I'm just looking to see if anyone else has a similar setup with an electric fan and can accurately report their experience with it. Obviously, I won't be going with something like underdrive pulleys anytime soon!
 

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Have you tried to use your A/C, stereo and headlights at the same time?

When I had the stock alt my car would let me know that my stock system was underrated and dated.

I also hope good wiring was used for the system and for the 3G upgrade.
 

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Discussion Starter #5
The car is not equipped with A/C, but I have frequently had the stereo blasting when stopped at a light with the headlights on and there is no noticeable headlight dim. As I said, I just see the voltage gauge dip a bit on really heavy bass hits, but I don't know if it's an accurate reading or just something odd with the gauge itself.

As for the wiring, I chose the ideal size and quality of wiring for this particular application. 4-gauge wiring from battery to amps and I upgraded to a larger set of power wires for the alternator. Short of going out to test the amperage draw on the system myself (which I can't do until I take the car out in the Spring), I was hoping there would be at least one other person on these forums who has an electric fan and a beefy sound system running at the same time. If I get the all-clear from another member, I'll consider ordering the fan kit soon and installing it before I take out the Mustang.
 

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I have an PA 130 amp alternator, with a electric fan, better head lights and now a ok stereo and it does great. If you really have a "beefy sytem" this is what you really need


Shop for farad capacitor car audio on Google
 

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Discussion Starter #7
Thanks for the reply. It's good to hear that you have the electric fan running with a sound system, at least. Just out of curiosity, what are the rough specs of your stereo setup? How many amplifiers and what are their power ratings? As for the capacitor, I mentioned in my first post that I have a 2 Farad capacitor hooked up already.
 

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no name amp rms 1000watts , two kickers rms 400watts and a kenwood something, Not sure what one it's older. But more than I need
 

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As for the capacitor, I mentioned in my first post that I have a 2 Farad capacitor hooked up already.

Sorry I didn't see that at 1st lol
 

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Discussion Starter #10
That's still a pretty solid system. Your subs and amp are almost the same as mine in terms of power, and those are typically the biggest drain on the electrical system. If you say you get no dim at idle with the sound system going, I'm almost convinced I can go with an electric fan too. Thanks!
 

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As I have a new baby girl I don't play it loud any more. But when she's not with me no issues that I've seen
 

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Discussion Starter #12
Congrats on the baby girl! One last question I guess while I have you here. How do you like the electric fan? Was there a noticeable difference in terms of horsepower gains or was it mostly negligible? For $250-350 I can think of a lot of other things I could do to the Mustang first if it's not really decent.
 

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Sorry it was bed time says the momma lol

As for if I felt any hp gains in short yes. But do it the right way. Buy a relay for the fan so it comes on when the car needs it to, and not when you just turn the key to on. As that will only cause more draw on the battery at start up. (NOT WHAT YOU WANT)

Bang on man :winks
 
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