rawbutt

Hi all.....

My stock alternator is about to give out and I'm considering going for a higher amp unit to replace it...possibly a 200amp Powermaster. I read a post somewhere that said to be careful when going to a higher amp alternator because it may cause problems with the PCM. Is there any truth to this?

Thanks in advance.

Guest47904

No but any alternator that has leaking diodes allowing AC out will definately effect the PCM regardless of it's size.

rawbutt

speedy,

I don't much much about alternators and making sure I understand your point. Are you saying that my current one is prone to leaking so I am better off getting something new anyway? Or am I missing your point

Hotwire

you are missing the point. an alternator generates power using magnets and coils of wire. when the alternator is spinning it creates alternate current power, similar to what powers your household items, and no you can't plug anything in to the altenator. The altenator has a diode bridge which turns the ac (alternating current) into dc (direct current) that your car runs off of. Diodes are like little one way streets for power, put in the correct sequence they will turn a ac signal into a decent dc signal. If one of the diodes goes bad it will allow the ac to "leak" out into the dc wiring and start screwing w/ stuff that it's powering. nothing major you'll just notice stuff not running right and your lights pulsing at low rpms.

if you do go with a larger alternator, i would highly recommend alterstart down in tx. I ran one of their 180 amp alternators for over 4 yrs in my 97 s-10 abusing the crap out of it w/ a 800 watt system and never ever had a moments trouble out of them. I talked to Patrick, originally found them on ebay but dealt w/ them directly.

http://www.4alterstart.com/door/

rawbutt

Hotwire,

Thanks for the clarification....it definately helped. The only thing I really have drawing any extra current is a mild stereo. Not sure exactly how much the amp is rated for but I don't think it's not very much...it's just driving one 10" sub. Given this, do you think i should just go back with a 140amp or should I step up to 180-200 range? I certainly don't want to throw money away but would rather do it right the first time. I am fighting a few drivability issues with my recent 383 stroker rebuild and want to make sure I get a good enough one so that I feel like I can rule it out as a culprit of anything. I also really don't want to have any installation issues if I can help it....would rather the new one just bolt right into where the old one was with the existing mounting stuff in there. Any ideas?

Hotwire

the alterstart will bolt right in, but as far as your application, sounds like the stock 140 should run everything fine. If you do plan on running a larger stereo or electric water pump, I'd upgrade to stay on the safe side. If you do upgrade be sure to get the larger cable for your ground and battery leads.

You can take the car up to auto zone or advance auto, they will do a charging system diagnostics for free, or if you have the system apart you can carry the battery and alt in there and they can check each one independently.