In article IVbzb.26297$Bk1.22835@fed1read05,
"SHRED©" wrote:

I am on my 4th alternator in my 1991 Integra.
Napa autocare service centers are replacing them, under warranty, until now.
They referred me to an auto-electric shop. This shop claims that my car's
wiring is fine but the amplifier in my car is responsible for destroying the
Napa alternators.

I have an Alpine MRD-F752 5ch (75wx4 and 250wx1) driving 4 PA DX6's and a JL
Audio 12".

The mechanic at the auto-elec shop claims that he tested the amp and it is
drawing between 50-80 amps!! This is a 60amp rated alternator so with the
lights and A/C, etc..he claims the stereo is pushing it over the edge.

Wait a minute...Watts divided by volts= amps.
325w / 12v = 27amps..right?

Why would that Alpine be reading so high?

Why do my headlight dim with the bass note thumps even when not blasting?

I think it is a Napa alternator issue...as in junk.

I have to call them in the morning and let them know if I am going to remove
the amplifier. Damn I'd hate to do that it sounds so sweet.

WTF can I do? I am scrambling for electrical answers I know little of.

Why do my friends, in little Honda Civics and other vehicles, have no
problems driving 500 watts with the stock alternators?

Thanks



Class AB amplifiers are less than 50% efficient. That's where the
current is coming from, but 80A sounds high. Some of that might be
meter needle momentum.

You have a piece of crap alternator. Alternators are overloaded all the
time, it's normal. Every time you start your car, your alternator is
overloaded for at least a minute. Every time you start driving after
lengthy idling with the headlights on, the alternator overloads for a
while. Driving after getting a dead battery jumpered overloads the
alternator for about an hour.

Holding a partially discharged car battery at a perfect 14.4V would
require 100-300 hundred amps. That's not available so the alternator
has to be tolerant of being maxed-out for long periods. The only
problem you should ever have with too big of a stereo is gradual battery
discharge.

You're probably getting cheap-o alternators with poor air circulation,
undersized diodes, or bad connections to the windings. Get a better
brand and you'll be set.