bolt on alternator upgrade impreza wrx

Try rewiring the amp and putting in a 1 farad capacitor first.

Much easier, definately DIY.

-mark

Is this a second alternator or a replacement one?

Mickey

Good question. I'm not sure what i need. I didn't mention it before, but i'm looking for an upgrade for more output, not to replace a defective one. I've also heard of pulleys that change the speed of your alternator. are these any good or just snake oil?

Changing pulley size will change the efective range the alternator starts putting out rated capacity. On the other hand if you move up the speed at idle to get better power there you also move up the speed at max rpm of the engine where you are playing with the point where the bearings fail and/or the rotor flies apart. What are you really trying to make happen?

Refer to his previous posts; factory stereo is taking too much power from the dome light for his liking, IIRC.

Upgrade the wiring and relays, you don't need a new alternator. As I've said before, I've got a 98 Toyota Starlet that easily pumps out enough to power 200w driving lights, 200w high beam, 50w (total) park lights, 1000w sound system, for long periods without missing a beat. Tested battery voltage drops by up to 0.1v after half an hour to 45 mins of highway driving (Unconfirmed, crap multimeter was flicking between 12.8 and 12.9 at the battery both times, IIRC). Mileage unchanged from when it was just the high beams and stock stereo.

-mark

Take a look at this thread from over at NASIOC :

Thread is about replacement 160 amp alternators to cover such things as extra lighting and high power sound systems.

Unfortunately the link to Mid-west Electrical in the thread no longer works (and I don't know if they're still in business) but if you search around some more on NASIOC you'll probably find what you need.

I don't know why you keep talking about my amp. I'm talking about my alternator. I removed the stock subwoofer and installed a new amp and computer for gps/nagivation (new wiring from the battery) and want to install a second amp. I don't want to be rude, but I know that i'm looking for an alternator, not a wiring lecture.

Thank you for the post about the 160 amp alternator. I will look into it.

two issues - highway driving gets the alternator up to speed where it is putting out rated power 13.2v x 75 Amps = 990 watts. Basic physics says exceed that and you start draiing the battery. The more you exceed that by the faster the battery drains. 30 years ago I would bet there was more capacity in the alternator, today I would bet it barely sqeaks up to the spec. I would also bet that you seldom really use 1000 watts from your sound system. I'm not knocking they system, there are reasons why that peak power is good, but I would be very surprised to find out you are running a constant tone at any frequency at that power level for long periods. Anything else reduces the average power consumption. It is also a LOT of sound.

;-)

Install a second alternator. Or is it too cramped in there?

Al

I've been following this thread as I was also looking for a similar "bolt on upgrade" for the alternator(OBW though).

My reasoning is that I have a PC running GPS, mapping, stereo functions, and a few more things(only when the car is running), but it uses almost

300W constantly while doing that, plus the stereo(fairly big), and everything else that runs off it.

Thanks, that's true, the alternator is only putting out 75 amps at high speeds, and just because my amp is 1000 watts doesn't mean i'm using NEAR that. In fact, i'm only looking to fix the worse case scenario, and that is the music player, computer-gps/mp3s on, and idling. Currently when i idle and the headlights are on, the sound goes out for a second. New heavy duty battery and new wiring from the battery to my electronics. THe only thing left is to upgrade the alternator. I'm not looking to run FOH for deep purple, i just want to comfortably run some accessories while idling. I was inquiring if an alternator upgrade/addition is a DIY job or if i should take it to the shop. And if anyone had suggestions on a specifi unit, maybe a

150 amp?

Thanks again to everyone for their input

How does that work? One connected to the accessories, or both alternators connected ot the battery? Do you need two batteries then?

you could always get the original one rewound. or you could just bump the idle speed up 200rpm, that should also do it.

two alternators supplying a decent load will make your automobile a wee bit slower, btw. think aircon on/off differance, depending on how much load.

-mark

That may be a good possibility. What kind of place does this? Any chain store, or mechanic, or do i need an alternator specialist? I'm in the DC area if anyone has any specific suggestions.

thanks again

Try asking an upscale car audio place. You know, the kind of place where those nuts go to get a 5000W competition sounds system. They'd know how to get the most out of any car's charging system. Explain the situation and see what happens. Best Buy won't have a clue, but I bet a real enthusiastic car audio guy would know.