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200Amp alternator on a stock system?

CSVT#49

CSVT#49

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Joined
May 28, 2004
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Location
Andover, MN
I'm just curious about this idea. I plan to install a 200Amp high output alternator on my SVT, however my car (for the most part) is stock. I'm running a Dual DVD head unit with a 7" flipup screen and Rockford Fosgate 3way speakers. However I have additional plans for the future (running two batteries for one). However what I want to know is, are there any potential problems with running a high output alternator on a near stock electrical system??
 
Not sure, but I kinda think the car only "takes" what it needs from the alternator. I mean, even with the stock alt, your car isn't ALWAYS using all 130 amps, and that doesn't hurt it any. So I would guess that you'd be ok having the HO alt, even if you didn't "need" it yet. But again, I'm not 100% positive on that, so you may want to wait for other facts/opinions.
 
heck my talon had like a 75 amp alt and that lasted a while with my system in it...then when i had it rebuilt they upped the bushings to 95 amps. so 130 is good enough, cause I asked this before as well LOL. Running my head unit, harddrive mp3 player, two amps a 1000 watt sony (yeah I know, it isn't a 1000) and a 400 watt alpine, two 1000 watt sony subs (once again i know LOL), and 3 sets of speakers. never had one problem.
 
Just to update this... I talked with an electrical engineer here at my work since I'm not to familiar with charging systems. He told me that I would not have problems with going to a 200Amp alternator as the voltage regulator should prevent any issues, barring a few things.

He said I needed to check to see the charging curve, amps versus RPM's. Because you do not want to be turning the alternator so fast that you are pushing it beyond the 200Amp point.

Also he said to check the pulley size to make sure that the correct one is being used to obtain the required RPM to charge the system adequately.

So I'm going to look into these two things and determine if I will have issues, I'm guessing not at this point.
 
If you are going to be in stop and go traffic, DON'T PUT IN A 200 AMP ALTERNATOR. I bought one a while back and it sucked. I had to put an overdrive pulley on the alternator just so that I could BARELY hit 13 volts at idle. Unless you are severely discharging your battery with your stock 130-140 amp alternator, don't do it.

You'd have to be pulling 1500 watts continuously to max out your stock alternator. If you are doing that, you are gonna be one deaf MOFO.

If your lights are dimming, upgrade your battery feed to 0 gauge wire and put a 2 farad cap in back right before your amps.

HTH,
BP
 
It's not for an audio system. I'll be installing another battery in the trunk, which will be getting drained quite frequently. So at points I will be charging two batteries.

You can over come the problems you are having by decreasing the size of the alternator pulley.
 
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Actually you'd need a smaller pulley on the alternator. Or a larger pulley on the crank. ;)

I did the math and my alternator was hitting 17,000rpms at redline. :shocked:

...and it still wasn't fast enough to keep the voltage above 13V at 800rpms.

If you need so much current, why not ditch the AC and mount a massive 250 amp alternator down there? Also, what's the application?

BP
 
Maybe a little off topic from what your talking about, but I was told of a business here in Madison that the guy will re wrap your wires in your stock Alternator for X number of dollars per amp increase, but I don't remember the name of the place.... :(
 
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